Three people were killed when a gunman screaming Allahu Akbar shot at police and took hostages in a supermarket in southwestern France on Friday and Prime Minister Edouard Philippe said the incident appeared to be a terrorist act.

Police later stormed the supermarket in the small town of Trebes and the attacker was killed, Interior Minister Gerard Collomb told reporters on site.

A source at the Interior Ministry said two had died at the hostage-taking. “It is a provisional assessment as it could, unfortunately, get worse. Three people are wounded, including one of them seriously,” the source said.

Later, a police union official said the attacker had also killed one person with a bullet in the head in the nearby historic town of Carcassonne before the hostage-taking.

The station reported that the hostage-taker has claimed allegiance to Islamic State and that he has demanded the release of Salah Abdeslam - the prime surviving suspect in the Islamic State attacks that killed 130 people in Paris in 2015.

More than 240 people have been killed in France in attacks since 2015 by assailants who pledged allegiance to, or were inspired by, Islamic State.

The man first shot at four police officers in the historic town of Carcassonne before barricading himself in the Super-U supermarket in Trebes, about 8 km (5 miles) to the east.

A police union official said the attacker had killed one person with bullet in the head in Carcassonne before the hostage-taking.

Menassi also told LCI TV that the man had entered the shop in Trebes screaming “Allahu Akbar, (God is greatest) I’ll kill you all”.

Philippe said: “All the information we have as I speak lead us to think that this would be a terrorist act.”

Radicalised militant

Carole, who was shopping at the supermarket, described how people had taken refuge in a cold room.

“A man shouted and fired several times. I saw a cold room door, I asked people to come and take shelter,” she told Franceinfo radio. “We were ten, and we stayed an hour. There were more gunshots and we went out the back door.”

French investigators believe they have identified the hostage-taker. The man is known to the intelligence services and flagged in a database of radicalised Islamist militants, Franceinfo reported.

Police in helmets and body armour took up positions around the Super-U supermarket.

The Paris prosecutor’s office said counter-terrorism prosecutors were investigating the incident but did not comment on the possible Islamic State allegiance.

Earlier, the Interior Ministry had said security forces were carrying out an operation at a supermarket in southern France. Interior Minister Gerard Collomb was on his way.

The UNSA police union also said on Twitter a police operation was underway after an individual had earlier shot at four officers in the Carcassone region, wounding one of them.