French police have arrested a total of six men in their investigation into last Thursday’s attack on the Basilica of Notre-Dame de l’Assomption in Nice.

Among those in police custody is a 29-year-old Tunisian man believed to have accompanied the alleged attacker, Brahim Issaoui, from Tunisia to the Italian island of Lampedusa on Sept. 20, Agence France-Presse reported Nov. 2.

The 29-year-old was arrested in Grasse, southern France, Oct. 31 and taken in for questioning, as were two other men, aged 25 and 63, living at the same address. One man has since been released, while the others remain in police custody, according to AFP.

The attacker stabbed three people to death inside the Nice basilica on Oct. 29. The victims were Simone Barreto Silva, a 44-year-old mother of three; Nadine Devillers, 60; and Vincent Loques, the church’s 55-year-old sacristan and a father of two.

French police shot and arrested the perpetrator, who was identified as the 21-year-old Brahim Aouissaoui, based on an Italian Red Cross document he was carrying. He had an additional two knives and a Quran in his backpack.

The police investigation indicates that the young Tunisian man had arrived in Nice on the night of Oct. 27 on a train from Rome, according to the Guardian. His family in Tunisia later confirmed to journalists that Issaoui is the correct spelling of their last name.

The police also arrested a 47-year-old man on the day of the attack who was reportedly suspected of being in contact with the assailant. On Oct. 31, two men aged 33 and 35 were also taken in for questioning, however police did not provide any further details.

French president Emmanuel Macron visited Nice immediately following the attack.

He told journalists: “I want to say here first and foremost the support of the whole nation for Catholics, from France and elsewhere. After the assassination of Fr. Hamel in August 2016, it is once again the Catholics who are attacked in our country.”

Macron called Pope Francis on Oct. 30, saying that he wanted to tell the pope of France’s solidarity with Catholics and thank the pope for his support at a difficult moment for France, according to Aleteia. The French president also reiterated an invitation to Pope Francis to visit France.