The militant Islamist sect Boko Haram is suspected of killing at least 110 people of various faiths across Nigeria during the past week, prompting the country's top Catholic bishop to declare the rebel movement "has no limits".

Last Thursday, gunmen killed Reverend Augustine Yohana, a Catholic priest, and two of his sons in Nigeria's northeastern state of Yobe, then set their home and church building ablaze. The Nigerian news service Daily Trust quoted one of Yoahana's surviving sons, Ibrahim, as saying the gunmen arrived in their town of Garinbaba in the middle of the night, "woke us up, asked us to lie down in front of the church, tied our hands with rope and said they are security personnel on search mission".

No arrests have yet been made.

A Christian leader in the area, who asked that his name not be used to help preserve his safety, told World Watch Monitor the attackers were members of Boko Haram.

"My life and that of many other Christians in the state is in danger and we are only hoping that the government will take necessary measures to stop these endless killings in the state," he said.

In the neighbouring northeastern state of Borno, suspected Boko Haram attackers raided the town of Gamboru twice. The first attack, on the night of Wednesday, September 25, killed six. The second, late Thursday, killed a further 21.

On Saturday, in the central state of Kaduna, gunmen moved into the town of Zangang in the early-morning hours, burned homes and killed 15 people. Hundreds of residents fled the village. Guardian News Nigeria cited a survivor of the attack as saying most of the victims were young people on their way into the farm fields. The Northern States Governors Forum has said it suspects Boko Haram of the attack.

Then, at about 1:30 am Sunday, about 30 gunmen stormed the Agricultural College campus in Gujba, Yobe state. They roused the sleeping students, gathered them into a single place, and shot them. News accounts vary about the number of students killed, initially putting the death toll between 40 and 50, and later increasing it to 65. Several other students were injured, and many dodged gunfire as they fled into the surrounding countryside.

Some of the college buildings were set on fire. After visiting hospitalied victims Sunday, a tearful Yobe Governor Ibrahim Gaidam implored Nigerian security forces to improve vigilance against violence.

Monsignor Ignatius Ayau Kaigama, Archbishop of Jos and president of the Bishops Conference of Nigeria, on Monday issued a statement that noted most of the victims of the attack at the college were Muslim.

"In the beginning the aim of Boko Haram was to attack Christians in order to destabilise the community. But now the ferocity of the members of this movement has no limits to the point of slaughtering even those who should be their fellow Muslims," Kaigama said through the Catholic news service Agenzia Fides.

"Boko Haram has made further progress in the sophistication and ferocity of their attacks but it is now made up of fanatics who have lost their original goal."

The leadership of Boko Haram has declared its intent to wipe out Nigerian democracy and replace it with an Islamic state guided by sharia law.

Pastor Ayo Oritsejafor, president of Christian Association of Nigeria, and others condemned the killings and urged the federal government to intensify efforts to stop the Islamic insurgents that have killed thousands of persons in the northern parts of the country.

"There is fear and apprehension in the length and breadth of this nation, but Jesus said: Take courage," he said Sunday at a service to mark Nigeria's 53rd year of independence.