At least 40 people were killed and about 100 wounded in suicide bomb attacks in Morocco's biggest city Casablanca on Friday night, diplomatic sources in the capital Rabat said on Saturday.

Among the targets were a Jewish community centre and a Spanish club and restaurant in downtown Casablanca.

No group has claimed responsibility for the attacks.

"International terrorism struck Casablanca tonight," Moroccan Interior Minister Al Mustapha Sahel was quoted as saying by 2M television in the early hours of Saturday.

This was the first major attack of its type in Morocco in recent years and followed suicide bombings of expatriate housing compounds in the Saudi capital Riyadh on Monday that killed 34.

Like the Riyadh assault, Osama bin Laden's Al Qaeda was the prime suspect in Casablanca. A US official said it was 'plausible' to suggest that the group Washington blames for the September 11 hijacks was behind the latest coordinated attack.

Sahel said the terrorists struck at the Hotel Safir in the old heart of the city, a Jewish community centre, an old Jewish cemetery and the Casa de Espana Spanish social club. Local journalists said the bulk of the dead were at the club.

"There are body parts all over the place," Moroccan journalist Aboubakr Jamai told the BBC, describing an eyewitness account from the Spanish restaurant, where one report said a young attacker had blown himself up with a grenade in his belt.

The Belgian embassy in Rabat said two policemen outside its Casablanca consulate were killed and a security guard wounded. The five-storey building, which stands across the street from a Jewish-owned Italian restaurant, was badly damaged.

A police officer outside the Jewish centre told Reuters at the scene that the attack there was "apparently carried out by suicide bombers who were wearing explosives around their belts". He had no information on casualties.

The single-storey building was badly damaged, with blood stains visible on the facade up to five metres high. Broken glass, bricks and rubble littered the street.

In Madrid, a Spanish diplomat quoted colleagues in Morocco as saying that three people with explosives entered the Spanish restaurant. Spain was a vocal supporter of the US war on Iraq and has had fraught relations with Morocco, where Madrid once exercised colonial powers.

Spanish diplomats said one of the explosions had hit either the office or residence of the US consul, which lies close to the Belgian mission. In Washington, a State Department spokesman said no US government facility was hit.

Casablanca, Morocco's biggest city with a population of 3 million, lies on the Atlantic coast about 60 miles (95 km) southwest of the capital Rabat.

In February, Morocco jailed three Saudis for 10 years for taking part in what the court found was an Al Qaeda plot to attack US and British warships in the Gibraltar Strait.

In August last year, the authorities -- who keep tight control over Islamist activity in the kingdom -- arrested 30 radical Islamists for allegedly killing several Moroccans.

Al Qaeda claimed responsibility for a truck bomb attack on a synagogue in another North African country, Tunisia, in April last year in which 20 people -- including 14 German tourists -- were killed. Neighbouring Algeria has been riven by Islamist violence against the government for over a decade.