MAIDUGURI, Nigeria (AFP) – Nigerian authorities cleared bodies on Saturday from the streets of a northern city where troops crushed an Islamic sect's uprising, as police arrested dozens of the group's members.

Police said they arrested 36 suspected members of the sect, including two from neighbouring Niger, this week after attacks by extremists and fierce gun battles in the city of Maiduguri.

More than 600 people were killed in the violence, including the 39-year-old leader of the self-styled Taliban group, Mohammed Yusuf, 39, who was shot dead by police on Thursday after being captured.

Police also said Saturday they had rescued 230 young women and children kidnapped from several northern states and brought to the northeastern city of Maiduguri during the uprising.

One girl among them, Maimunatu Shuraim, 15, told AFP that the sect members herded them into buses telling them they would learn "pure Islamic theology" in Maiduguri because "Western education has been responsible for the immorality among the youth."

The 36 suspects were arrested Thursday as they headed west for Lagos, the economic capital, from the capital Abuja, according to a statement by Abuja police chief Haruna John read out to reporters by his spokesman, Jimoh Moshood.

The Saturday Punch newspaper published a picture of the suspects, most of whom appeared to be very young men.

In Maiduguri, scene of the worst of this week's violence, an official of the International Committee of the Red Cross, Halima Bulama, expressed concern about the risk of disease from the decaying corpses.

"We are really worried about a possible outbreak of diseases like cholera due to the presence of decomposing corpses on the streets of Maiduguri which is constituting a serious health risk," she told AFP Saturday.

Her colleague, Ibrahim Aliyu, said: "the task of picking (up) the decomposing bodies has started in earnest and it is going on well." He did not say how many bodies had been picked up so far.

On Saturday morning, authorities searched cars and questioned passers-by in the city, where an AFP reporter saw more than 30 decomposing bodies in three different districts.

Government spokesman Usman Chiroma said: "The government is making efforts to evacuate the dead bodies from the streets of Maiduguri. We have mobilised men and equipment for this job.

"However, it is an enormous task given the paucity of our human resources," he told AFP.

Dozens of armed soldiers and riot police guarded strategic points in the city, where troops carried out a fierce assault on the base of the so-called "Taliban" movement this week.

Clashes in four northern states killed more than 600 people, according to police and witnesses.

The air was pungent behind Maiduguri's main government hospital, whose morgue, according to hospital sources, was overflowing with corpses.

A grocer in the area, Usman Madi, 35, said: "We pray that authorities either give these decomposing bodies a mass burial or make a public announcement for relations to pick them up for burial."

The chief of defence staff, Air Marshal Paul Dike, on a visit to Maiduguri on Friday, vowed that "the military will leave no stone unturned in ensuring that no such incidents occur."

"We have the capability to crush any breach of Nigerian security," he said.

The killing of the sect's leader was condemned by human rights groups including Amnesty International.

A senior police officer said Yusuf was killed in a shootout as he tried to escape, but another officer said the sect leader had pleaded for mercy before being gunned down.

Information Minister Dora Akunyili said the shooting of Yusuf had prevented violence from spreading across the country's Muslim north. "It's the best thing that could have happened to Nigeria," she told AFP