France needs to create special courts and detention facilities for citizens suspected of having links to terrorism, former president Nicolas Sarkozy has said in a Sunday newspaper interview.

Sarkozy told Le Journal du Dimanche: “Every Frenchman suspected of being linked to terrorism, because he regularly consults a jihadist website, or his behaviour shows signs of radicalisation or because he is in close contact with radicalised people, must by preventively placed in a detention centre.”

Sarkozy, who announced last month his candidacy for the April 2017 presidential election, has said there is no place for “legal niceties” in the fight against terrorism.

The French capital was once again on high alert on Sunday last week after a car loaded with gas cylinders was found near Notre Dame cathedral in an incident that could have been intended as an attack on a Paris railway station.

Security is a key topic in the presidential elections in 2017. More than 230 people have been killed in militant Islamist attacks on French soil since January 2015.

Sarkozy’s comments come after the French president, Francois Hollande, a Socialist, took a swipe at his opponents this week, saying their hardline reactions to a wave of militant attacks demonstrated an intent to destroy France’s social model.

According to French Institute for Public Opinion, voters have most confidence in former prime minister Alain Juppé to guarantee security, with Sarkozy in second place, Prime Minister Manuel Valls in third, and Hollande a distant 8th.

The French justice minister, Jean-Jacques Urvoas, said in a separate interview with the French newspaper on Sunday he planned to make proposals next week to Valls to ease prison overcrowding.

“I do not advocate creation of facilities dedicated to terrorists ... The real challenge is to prepare the release of those who are sentenced for a short or medium term,” Urvoas said.