COTABATO (Philippines) - SHOPS, restaurants and schools shut down in the large southern Philippine city of Cotabato on Friday in protest over a deadly bombing blamed on Islamic militants, eyewitnesses said.

Hundreds of protesters trooped to Christian churches and Muslim mosques across the city to listen to religious leaders condemn Sunday's bombing that left six people dead and more than 50 others wounded, they said.

'It's like Good Friday,' Araceli Abellera, a sidewalk vendor told reporters, referring to the holiest day of the Catholic calendar, as she looked down a long line of shuttered shops along the main road of the Christian-Muslim city of 155,000.

Many of the shops displayed banners condemning the bombing and frequent kidnappings that have mainly targeted the city's shopkeepers and their families.

President Gloria Arroyo cancelled a planned visit Friday to Cotabato, which is on the troubled island of Mindanao, and her spokesman Cerge Remonde said the city government also closed for the day 'as a gesture of sympathy to the victims of (the) bombing'.

An improvised explosive device ripped through a butcher's shop outside Cotabato cathedral on Sunday in an attack blamed on a hardline faction of the

Moro Islamic Liberation Front (MILF), which denied responsibility. The MILF has led a decades-old rebellion across the country's south that has claimed thousands of lives. The region has since spawned a new generation of Islamic militants allied to the Al-Qaeda network.

Oscar Tan Abing, president of the Cotabato Grocers Association, said shopkeepers agreed to close shop for one day in protest at the violence and kidnappings.

Local hospitals were on a sympathy strike, though emergency rooms 'remained open,' said Johnny Rabago, an official at the industry group the Philippine Medical Association.

Cotabato Catholic Bishop Orlando Quevedo, in a pastoral letter read in local churches on Friday, called on the authorities 'to expedite the identification, arrest and detention of the perpetrators'. -- AFP