Two Lebanese suspects alleged to be members of Hizbullah and on trial in Nigeria on terrorism charges told a court Monday they were harshly interrogated by Israeli agents after their arrests.

Mustapha Fawaz, Abdallah Thahini and Talal Ahmad Roda were arrested in May after the discovery of an arms cache in a residence in the northern Nigerian city of Kano.

The death toll in a gun attack on the convoy of Emir of Kano, an influential Nigerian Muslim figure, has risen to five, the police said, as the monarch and his injured sons flew out of the country on Sunday.

"The interim chairman of Kura local government and his driver were also killed by some gunmen who pursued them from the scene of the attack" on Emir Ado Bayero, Kano police spokesman Magaji Majia told Agence France Presse.

Explosions rocked parts of the northeastern Nigerian city of Maiduguri Saturday as troops engaged suspected Islamic radicals and raided homes, residents said.

The explosions, which began late Friday, occurred in three neighborhoods notorious for attacks blamed on the Boko Haram sect, and residents fled as troops went door-to-door arresting people suspected of complicity, they said.

Nigerian troops raided Tuesday a suspected hideout of Boko Harem used for its violent attacks in the northern city of Kano, killing one Islamist and recovering some arms and ammunitions.

An Agence France Presse reporter who visited the scene said a military task force stormed the two-bedroom bungalow at Bubbugaje in the outskirts of the city around 4:30 am and engaged the insurgents in a shootout.

Attackers armed with bombs and guns opened fire at outdoor church services at a Nigerian university Sunday, killing around 20 people as worshippers tried to flee, witnesses and officials said.

A powerful explosion and gunfire rocked Bayero University in the northern city of Kano, with witnesses reporting that two church services were targeted as they were being held outdoors on the campus.

Explosions and gunfire rocked a suburb in northern Nigeria's largest city of Kano early Wednesday where Islamists staged deadly attacks in January, an Agence France Presse reporter and residents said.

An AFP correspondent heard at least six huge explosions followed by gunshots, just before Muslim dawn prayers, which continued for around an hour.