Indonesian police were hunting for Islamist militants Friday after a terrorist attack in the capital killed two civilians, as security was tightened across the country. 

Five men armed with explosives and handguns attacked a police post and a Starbucks cafe near the Sarinah shopping centre in the heart of Jakarta on Thursday, killing one Canadian and an Indonesian.

Two of the attackers blew themselves up while the other three died in a shootout with police, officials said. Twenty people were injured, including one each from Germany, Austria, Algeria and the Netherlands. 

"We are in the pursuit of other cells and actors," Jakarta police chief Tito Karnavian said.

National police spokesman Anton Charliyan said authorities across the country were on the highest alert. 

"Security has been beefed up in government offices, police stations, embassies and malls," he said.

National police chief Badrotin Haiti said one of the dead attackers was identified as Afif, who was sentenced to 7 years in 2010 for terrorism but was released early. 

Afif was photographed pointing a gun at the crowd on Thamrin Street, wearing a baseball cap, a pair of jeans and a backpack containing explosives.

Moments later he blew himself up along with another attacker in the Starbucks parking lot while engaging in a shootout with police.

Charliyan said another dead attacker, whose name was not revealed, was also a former terrorism convict. 

Police have blamed a group led by Bahrun Naim, an Indonesian militant who is now thought to be in Syria fighting alongside the Islamic State group. 

Bahrun celebrated the November Paris attacks in a blog post and encouraged militants in Indonesia to do the same.

Officials said Bahrun had instructed operatives in Indonesia to attack police and places frequented by Westerners at Christmas and on New Year's Eve. 

Jakarta police spokesman Muhammad Iqbal said three people arrested on the city's outskirts early Friday were not linked to the attack, but were questioned for alleged extortion.  

Police in the city of Balikpapan in East Kalimantan province said they had arrested one suspected militant, but it was not clear if he was related to the Jakarta attack, Antara said.  

President Joko Widodo, who visited the scene of the blasts again on Friday, said on Twitter that "there is no place for terrorism in Indonesia."

"All citizens of the world must unite to fight it." 

His call appeared to be heeded by fellow Indonesians. 

Dozens of people, some carrying flowers, rallied at the scene of the Jakarta attack and shouted in unison: "We are not afraid!" and "Fight terrorists!" 

Indonesians also spread a message of defiance on social media with hashtags such as #WeAreNotAfraid and #JakartaBrave on Twitter. 

They also shared photos of how people near the scene of the attack went about their business as usual hours after the events, including one showing a satay vendor busily serving customers just a stone's throw away. 

Islamic State claimed responsibility for the attack, the militia's news agency al-Amaq said.

"A platoon of the Caliphate soldiers in Indonesia targeted in Jakarta a crowd of citizens from the Zionist alliance that fights Islamic State," it said.

The post said that at least four gunmen with light weapons and explosive belts killed at least 15 people.

The authenticity of the post could not be verified independently.

European Union foreign policy chief Federica Mogherini said the attack was a "tragic reminder that the threat of terrorism is global and has to be tackled globally."

Indonesia has faced problems in recent years with extremist violence, often linked to Islamist groups, and it is estimated that hundreds of its citizens have joined the Islamic State group in the Middle East.

Police last month arrested nine suspects they said were planning coordinated attacks on New Year's Eve.

Related stories

Indonesian police pursue militants after Jakarta attack

Indonesia blocks radical websites after attack

Bomb and gun attacks rock Indonesian capital

Four civilians died in Jakarta bombings, police say

Latest news

Syrian opposition rules out future role for President al-Assad

The Syrian opposition said Friday it would not accept any role for President Bashar al-Assad in the future of the war-torn country, reacting to a recent US shift saying that removing al-Assad is no longer a priority for Washington.

Russian Army integrates breakaway forces of Georgian province

Parts of the small fighting forces of the Georgian breakaway province of South Ossetia have been placed under Russian military control, Russian Defence Minister Sergei Shoigu said on Friday.

Czech Republic's Pilsner Urquell beer is now Japanese

Japanese brewing company Asahi completed its takeover of the Czech brewery Pilsner Urquell on Friday, Asahi said in a statement.

Judge approves 25-million-dollar settlement of Trump University case

A US district judge on Friday approved a 25-million-dollar settlement of lawsuits and state fraud allegations against Trump University, the US president's now-defunct business venture.

Former Thai premier Thaksin to junta on reconciliation: 'Cut me out'

Former Thai prime minister Thaksin Shinawatra on Friday announced that he is not interested in the junta-led reconciliation process, three days after the junta handed him a half-a-billion-dollar tax bill for his past business deal.

Dalic: We welcome possible deal between Agrokor and banks

The government welcomes the possibility of an agreement being concluded between the Agrokor food company and creditor banks, and the bill on vitally important companies is not a fallback plan but the result of the government's care for the overall economic and financial stability of Croatia, Deputy Prime Minister and Minister of Economy Martina Dalic told a press conference in Zagreb on Friday.

Croatia, China sign action plan for cooperation in agriculture

The Croatian and Chinese ministries of agriculture on Friday signed an action plan for cooperation in the field of agriculture for the period 2017-2018, the Croatian ministry said in a statement.

ZSE indices up, Agrokor shares in focus of investor interest

The Zagreb Stock Exchange (ZSE) indices on Friday rose by more than 1.8%, with stocks of the Agrokor food and retail concern being in the focus of investor interest again.

Berlin police defend handling of Berlin market attacker

Berlin police defended themselves on Friday against accusations that they stopped surveillance on Berlin Christmas market attacker despite knowing in June 2016 he was dangerous.

Croatia, creditors tailor emergency measures to save tottering giant

Croatia's tottering retail and food giant Agrokor reached an agreement with its creditors, putting its debts standby and allowing it to continue working during emergency restructuring, the Croatian branch of Austria's Erste Bank said Friday.

Agrokor's creditors say standstill agreement to go into force today

A standstill agreement regarding the Agrokor concern's existing financial obligations to banks will take effect on Friday, additional capital will be injected into the concern in the coming days and the concern will be actively restructured, which includes a change of its management, it was said on Friday after a meeting between Agrokor's suppliers and creditor banks.

Palestinians, UN slam Israel's new settlement plan

Palestinians, Israeli activists and the UN lambasted the government of Israeli Prime Minister Benjamin Netanyahu on Friday, a day after it gave the go-ahead for the first new West Bank settlement in a quarter of a century.

South Sudan rebels release three abducted foreign oil workers

South Sudanese rebels have released three foreign engineers they abducted in early March in the oil-rich Upper Nile region, Foreign Affairs Ministry official Mawein Makol Arik said on Friday.

Turkish opposition: Imprisoned party chief has gone on hunger strike

The head of Turkey's pro-Kurdish opposition party has launched a hunger strike from prison.

European leagues threaten Champions League schedule clashes

The European Professional Football Leagues (EPFL) on Friday threatened schedule clashes on Champions League matchdays in an ongoing dispute with the governing body UEFA.

Danish court revokes citizenship of IS volunteer

A Danish appellate court on Friday stripped a man of his Danish citizenship for volunteering to fight for the extremist Islamic State in Syria.

Banks and Agrokor agree on key elements of standstill agreement

Member banks of the coordinating committee of financial creditors and representatives of the Agrokor food company have in principle agreed on key elements of a standstill agreement, which is expected to be signed later today, announcing changes in the company's management team, Erste Bank said in a statement on Friday afternoon.

Syrian man on trial in Sweden; mosque attack labelled terrorism

A Syrian man went on trial Friday in the southern Swedish city of Malmo, charged with terrorism and arson after an attack last year on a building used as an assembly hall by Shiite Muslims.