Tunisian troops killed four suspected militants in a counter-terrorism operation overnight that was still continuing on Tuesday, the interior ministry spokesperson said.

There were no security force casualties in the operation in the Ain Jaffel area on the border between the central provinces of Kasserine and Sidi Bouzid, Yasser Messbah told press.

Kasserine province, which neighbours Algeria, has seen repeated clashes between security forces and militants.

Late last month, a suspected militant was killed in an exchange of fire in the Mount Mghila area of the province.

It lies next to Mount Chaambi, which is considered to be the militants’ main rear base and has been the target of repeated sweeps by the security forces since 2012.

Extremists have killed dozens of police and soldiers since the 2011 revolution that ousted longtime dictator Zine El Abidine Ben Ali.

Several attacks have been claimed by al Qaeda in the Islamic Maghreb.

But last year, the Islamic State group claimed attacks on the national museum in Tunis and a popular resort hotel, killing a total of 59 tourists, and the suicide bombing of a bus that killed 12 presidential guards.

The attacks, which have dealt a heavy blow to Tunisia’s tourism-reliant economy, are believed to have been organised from neighbouring Libya, where US aircraft carried out a deadly strike on their suspected mastermind last month.

Tunisia has built a 200-kilometre (125-mile) barrier that stretches about half the length of its border with Libya in an attempt to prevent militants from infiltrating.

Britain announced on Monday it was sending a team of around 20 soldiers to Tunisia to train troops patrolling the border.(Agencies)