CASABLANCA (Morocco) - NINE Islamic extremists convicted for the Casablanca bombings that killed 45 people in 2003, including one facing the death sentence, tunnelled their way out of a Moroccan prison early on Monday, officials said.

The Kenitra 'prison administration noted the escape on Monday morning and all measures have been taken to find the escaped prisoners and establish who was responsible', the justice ministry said in a statement quoted by the MAP state news agency.

The Casablanca bombings were Morocco's deadliest ever, killing 45 including 12 suicide bombers, and injuring scores more.

An official representing a prisoners' welfare group said the fugitives had escaped from Kenitra prison north of Rabat after dawn prayers at 5.30am (1.30pm Singapore time).

Mr Abderrahim Mahtade, president of the Annasir association, said one of the nine had been sentenced to death, six others to life imprisonment and two were given 20 years in jail. All were from Casablanca.

Describing how the nine had tunnelled their way out, an interior ministry source said details had been released to help the search. Border guards had been placed on alert.

Mr Mahtade said they had left a letter denouncing the injustice of which they said they were victims and explaining that having tried all legal avenues in vain, they were left with one option.

'We assume responsibility for our actions and there should be no search for accomplices among detainees or in the prison administration,' the letter said, according to Mr Mahtade. 'We will hurt nobody, but we are glad to get our beloved freedom back.'

A Moroccan suspected of making bombs for both the attacks in Casablanca and the 2004 train bombings in Madrid which killed 191 appeared before an anti-terrorist tribunal last week.

Saad Houssaini, 38, is suspected of 'threatening internal security' and forming a criminal gang with a view to prepare and carry out terrorist acts, MAP reported, quoting a judicial source.

Arrested in Casablanca in 2007, Houssaini appeared before the court in Sale south of Rabat with 18 fellow defendants, but the tribunal adjourned the case until May.

The court in Sale has begun trying 51 other suspects in more than half a dozen suicide bomb attacks in Casablanca in March and April 2007, after jailing three youths in March for complicity.

Those bombings killed a policeman and injured several people in working class parts of the city.

Many of an estimated total of more than 900 Islamic extremists detained in various Moroccan prisons went on a 24-hour hunger strike Monday in protest at their conditions.

Last December a drug baron called Mohamed Ouazzani, alias Nini, strolled out of Kenitra prison unhindered and the justice ministry was informed only a week later of his disappearance.

In January, eight prison guards received sentences ranging from two months to two years for abetting his escape.

Relatives of the fugitives expressed surprise and shock on Monday.

'I visited him only four days ago and he seemed quite normal,' said 66 year-old Touda, mother of Abdelhadi Dahbi, 50, on death row for murdering a policeman.

Ms Touria Chatbi, 37, despaired of ever again seeing her brothers, Kamal, 25, and Mohamed, 35, each given 20 years. She said they had already been arrested in 2002 on returning from Spain where they had been staying with their mother.

She said the police had also arrested her father on Monday.

The mother of Hicham al Alami, sentenced to life imprisonment in August 2003, fainted on hearing the news of her son's escape.

Later she joined a demonstration outside Okacha jail in Casablanca against prison conditions there. 'I felt as though I had just been told of his execution,' she told fellow-demonstrators.

Many of the 900 extremists currently in Moroccan custody went on hunger strike on Monday in solidarity with prisoners in Okacha, Berrechid and Mohammedia prisons, who have been refusing food for three weeks in protest against conditions, said Mr Mahtade of the prisoners' welfare association. -- AFP