By Emmanuel Jarry

PARIS (Reuters) – French counter-terrorism investigators questioned five people on Tuesday after police over the weekend found what appeared to be a ready-to-detonate bomb at an apartment building in one of Paris’s poshest neighborhoods.

Interior Minister Gerard Collomb said one of those arrested was on an intelligence services list of “radicalized” persons – a list that includes the names of potential Islamist militants.

“We are still in a state of war,” Collomb, speaking after a Sunday attack in which a man stabbed and killed two women outside the train station in Marseille, told France Inter radio.

Judicial sources said the explosive device included two gas canisters inside the building in the affluent 16th district of western Paris and two outside, some of them doused with petrol and wired to connect to a mobile phone.

More than 230 people have been killed in attacks by Islamist militants in France over the past three years. The Islamic State militant group, whose bases in Syria and Iraq are being bombed by French war planes, has urged followers to attack France.

Most of those killed died when Islamist gunmen and suicide bombers targeted Paris in 2015, and when a man drove a large truck into crowds in the Riviera resort of Nice in 2016.

Since then, there has been a string of attacks perpetrated by lone assailants, often targeting police or soldiers.

“The threat is changing form,” said Collomb.

A counter-terrorism investigation is also under way after the attack on Sunday, when a man slit the throat of one of his victims and killed her cousin before being shot dead by soldiers in the southern port city.

Tunisian authorities have identified the attacker as Ahmed Hanachi, Collomb told parliament. He lived in France from 2005 to 2006 and was known to police under several alias’ for petty crimes, but had not previously caught the attention of French intelligence agencies.

Hanachi was arrested in the city of Lyon on Friday on suspicion of theft. He was carrying a Tunisian passport and released 24 hours later, a day before committing the attack.

“All these years, he used multiple identities in France as well as in Italy, declaring himself to be Moroccan, Algerian, Tunisian,” Collomb said.

France declared a state of emergency in late 2015 after the Paris attack, giving police special search and arrest powers to combat would-be terrorists.

Lawmakers will vote later on Tuesday on a bill to convert many of those emergency measures into common law.

(Reporting by Sudip Kar-Gupta, Brian Love and Emmanuel Jarry; Writing by Brian Love; Editing by Richard Lough)