The announcement comes two weeks after a known gun enthusiast rammed a car laden with weapons and gas canisters into a police van on Paris' Champs-Elysees avenue, the latest in a string of jihadist attacks to hit France since 2015.
The attacker, Adam Djaziri, was the only person killed, but the attack raised questions over how the 31-year-old was able to legally possess several guns despite having been flagged as a potential radical Islamist two years ago.
- France spells out four ways it plans to step up fight against terrorism
- Champs-Elysées attacker had gun permit despite being on terror watchlist
In an interview with Le Figaro newspaper two days after the June 19 incident, Collomb said he had asked for a probe into similar cases.
Collomb told a Senate hearing on a proposed new anti-terrorism law Wednesday that "we have identified about a hundred" individuals who like Djaziri were registered gun owners despite being on a watchlist for extremism.
"The person who wanted to commit that attack was on file and, at the same time, was the legal owner of firearms," he told senators. "This is a sign of dysfunction."
He said he had asked local police authorities to identify individuals on security watchlists so they are "able to take action and treat these problems" in order for the country to "return to a normal state".
France has been under a state of emergency since the November 2015 attacks in Paris, when Islamic State jihadists killed 130 people in shootings and bombings at the Bataclan concert venue, bars, restaurants and the national stadium.
The state of emergency has since been extended five times, but is set to expire in mid-July when the centrist government of newly elected President Emmanuel Macron is expected to extend it until November 1 while the new anti-terrorism law is prepared.