A man who attempted an attack on a Paris police station last week is thought to have spent time in an asylum shelter in Germany, prompting authorities in that country to investigate the link further.
Authorities in the western German city of Recklinghausen said Sunday they would give their full support to an investigation by the State Criminal Investigation Office.
"If we are able to contribute to explaining this matter further, then of course we will do this," the city's mayor, Christoph Tesche, said.
State police in North Rhine-Westphalia, where Recklinghausen is located, revealed late Saturday that the alleged attacker had previously lived in accommodation for migrants and refugees there.
The man was known to German authorities and had already served short-term custodial sentences for violation of gun laws, drug-trafficking and other offences, state police director Uwe Jacob said on Sunday.
He was shot dead as he attempted to storm a police building in Paris on Thursday while brandishing a meat cleaver and wearing a fake explosive belt.
Police had searched his former Recklinghausen flat earlier Sunday, acting on information from the French security agency. Officials said they found no evidence of any other planned attacks.
Following contradicting information on the suspect's nationality, French Interior Minister Bernard Cazeneuve confirmed that he is Tunisian, as was stated on the hand-written document found on his body.
In a previous police investigation related to a theft in Cote d'Azur in 2013, he had identified himself as Moroccan.
The man was reportedly registered in Germany under four different aliases, the Sunday edition of newspaper Die Welt said, citing unnamed security officials. He is thought to have applied for asylum in Germany under the name Walid Salihi.
Cazeneuve added that he is also thought to have spent time in Luxembourg and Switzerland before carrying out the attack on the anniversary of a terrorist siege of the Paris office of satirical magazine Charlie Hebdo.
The minister said that he had not yet independently confirmed the link to Germany.
The attacker is not thought to have had any accomplices.
Earlier in the year, he painted the emblem of the Islamic State terrorist network on the wall of his accommodation in Recklinghausen, according to the Die Welt report.
Weekly news magazine Der Spiegel reported that the man had been pictured there posing with the militia's flag, after which authorities flagged him as potentially dangerous. He disappeared from the hostel in December 2015, the report said.