The Cameroonian government has said its soldiers had killed "over 100" Boko Haram fighters during an attempted incursion by the Nigeria-based fighters into its territory.

The Cameroonian army has dealt "a severe setback" to Boko Haram, government spokesman Issa Tchiroma Bakary said in a statement read out on state radio on Monday, adding that the clashes took place in the north of the country on Saturday.

It was not immediately possible to independently verify the information.

According to the government statement, Boko Haram fighters fired two shells on the town of Fotokol in Cameroon's northern tip, on the border with Nigeria, at around 1:00 pm (1200 GMT) on Saturday.

"There were no casualties reported on the Cameroonian side after the attack," the statement said.

"Our defence forces responded vigorously with mortar fire aimed at the positions held by units of the Boko Haram terrorist group that was behind the attack."

"The Cameroonian response resulted in over 100 deaths among the aggressors," it said, adding that the fighters were forced closer back to the Nigerian border town of Gamboru Ngala, which Boko Haram seized over a week ago.

Gamboru Ngala is separated from Cameroon's town of Fotokol by just a bridge.

In recent days, residents from towns in Nigeria's northeast captured by Boko Haram have been fleeing across the border to Cameroon to escape atrocities by the armed group.