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.