A group of suspected Islamic militants¹ have attacked a jail in the southern Philippines, freeing at least 31 prisoners, prison officials say.

菲律宾狱警称，一群穆斯林武装嫌疑分子攻击了南部一座监狱，致使至少31人越狱。

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The jail in Isabela city where the inmates were freed

Two people, including a prison guard, are believed to have been killed during a gunfight as the prisoners escaped.

Basilan island's Vice³ Governor Al Rasheed Sakalahul told the Associated Press the gunmen had wanted to free Muslim guerrillas游击队员 held in the jail.

He said other inmates囚犯 had also escaped during the attack early on Sunday.

Mr Sakalahul said about 30 gunmen had used sledgehammers大锤 to break through the jail's concrete perimeter⁴ wall围墙 before using bolt-cutters断线钳 to cut through padlocks挂锁 on cell doors.

One of the prison guards was killed and another injured during the ensuing接着发生的 clash, provincial⁵ police chief Abubakar Tulawie told Reuters news agency.

'High-risk prisoners'

Regional military commander Maj Gen Benjamin Dolorfino told AP the 31 who escaped included suspected members of a Muslim rebel group, the Moro Islamic Liberation Front (Milf), and suspected militants from the Abu Sayyaf group.

Two Milf rebels accused of beheading a dozen soldiers on Basilan island in 2007 were among them.

"Those two rebel leaders are high-risk prisoners," Mr Tulawie said.

"We have organised a team together with the military units on the island to pursue them.

"We've started an internal inquiry⁶ to determine responsibility for the lax松懈的 security in the jail."

The escape came just hours before the country's Defence Secretary Norberto Gonzales was due to arrive on the island, which is 550 miles (880km) south of Manila.

He is facing calls for emergency rule to be declared on the island because of Islamist violence.

The jail, located in the provincial capital, Isabela city, has a history of jailbreaks.

Three Abu Sayyaf militants escaped from the prison last year, while 16 prisoners broke out in 2007.

Five years ago, 53 inmates overpowered制服 their guards using smuggled⁷走私，偷运 firearms and fled the prison.