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An explosion at an illegal World Cup viewing site in northeast Nigeria killed at least 14 people while security forces arrested a "terror kingpin" among nearly 500 people detained as suspected terrorists in the southeast of the country, police said Wednesday.

At least 26 people were wounded in Tuesday night's blast as soccer fans were viewing the Brazil-Mexico match in Damaturu, the capital of Yobe state, police said.

"The bomb just threw me away and I didn't even know where I was," survivor Babagana Mohammed said. He recovered consciousness in the hospital.

Another wounded victim, Musa Mohammed, said some people lost limbs in the blast. He said he had stopped by to buy airtime for his cellphone. "I stopped at the viewing center to buy a recharge card and suddenly the blast went off. It was just like a flash of light and many people were killed. Some were amputated ... But thank God mine was a lesser injury."

Witnesses said a suicide bomber drove a tricycle taxi packed with explosives into the area. But Police Assistant Superintendent Nathan Cheghan said the explosion came from a car parked and abandoned on the road in front.

Cheghan said such viewing sites were banned in Yobe state two months ago because they have become a target of Boko Haram, an armed Islamic group that wants to turn Nigerian into an Islamic state.

There was no immediate claim of responsibility but he blamed Boko Haram.

Security experts have warned that Islamic militants might attack crowds watching the World Cup in public places in Nigeria, Kenya and Uganda, as they did in 2010 in Uganda.  The explosions in Kampala, Uganda, at two sites where people watched the 2010 World Cup final on TV killed 74 people. Al-Shabab, a Somali insurgent group, set off those bombs.

Meanwhile, the Ministry of Defense said it has detained "a terror kingpin in the list of wanted terrorists."

A statement Tuesday night said he was found among 486 suspects arrested while travelling at night in a suspicious convoy of 33 buses in southeast Enugu state.

Local news reports have said the men and a handful of women detained said they were travelling from the north to Port Harcourt, Nigeria's oil capital in the south, to look for work.

Boko Haram's leader Abubakar Shekau has threatened to attack targets in the Niger Delta which produces much of the oil that makes Nigeria Africa's largest petroleum producer.

On Sunday, police discovered explosive devices hidden in a flower pot at the entrance to a church in southeastern Imo state. Police said they have arrested five suspects in connection with that failed bombing attempt.

Until this year, Boko Haram attacks were almost exclusively limited to northern Nigeria and concentrated in the northeast. This year, attacks blamed on the extremists have spread to at least four central states and have increased in frequency and deadliness. More than 2,000 people have been killed this year, compared to some 3,600 in the four previous years.

There are fears the insurgency could spread to neighboring countries where Boko Haram is known to have bases.

Its power has grown despite a year-old military state of emergency in three northeastern states covering one-sixth of the country, in part because the defense establishment is riddled with corruption that cripples nearly every facet of life in Nigeria.

The kidnapping of more than 250 girls two months ago and the failure of Nigeria's military and government to rescue them has roused international concern. The United States is searching for the girls with drones and has sent experts along with Britain and France to help in counter-terrorism tactics and hostage negotiation.

Boko Haram's leader has threatened to sell the girls into slavery unless the government agrees to exchange them for detained extremists, but President Goodluck Jonathan has said he will not exchange prisoners. Nigeria's military has said it knows where the girls are but that any military campaign could get them killed.