A Marrakesh explosion branded as a "terrorist" attack by Morocco and France killed at least 14 people on Thursday, including six French nationals, officials, medical staff and witnesses said.
As King Mohammed IV ordered an urgent probe, Moroccan officials said the explosion at the busy Argana cafe on the popular Jamaa el-Fna square may have been the work of a suicide bomber.
Medical sources put the death toll at 15, including six French citizens and three Moroccans, and said about 20 people were wounded, of whom seven French, two Dutch, two Swiss, to Russians and two Tunisians.
There was no immediate official confirmation of the toll from the blast at the cafe, a favourite haunt for foreign visitors to the tourist city about 350 kilometres (220 miles) south of the capital.
Rabat and Paris condemned what they said was a "terrorist" attack, with French President Nicolas Sarkozy branding it as "heinous, cruel and cowardly".
Sarkozy had spoken to the monarch on the telephone, his Elysee office said, confirming there were French casualties without giving any details.
France's Prime Minister Francois Fillon said diplomats in Morocco had been mobilised to provide support to victims and their families in coordination with local authorities.
The explosion happened "on the terrace" of the Argana cafe, Latifa Idrissi, the wife of 28-year-old waiter Yassine Bouzidi who was killed in the blast, told AFP.
One client recalled: "An individual came into the cafe. He ordered a glass of orange juice, and several minutes later, he blew himself up."
The facade of the cafe and the first floor were severely damaged, and tables and chairs strewn around the terrace.
A student who was inside the cafe recalled hearing three loud detonations and seeing victims flee.
"A woman was blown into the air and I saw a man completely disfigured," the student told AFP by telephone. "Then I saw a girl 14 or 15 years of age, she was also disfigured. The three were foreigners," he said.
Morocco's Communications Minister Khalid Naciri told AFP this was "a terrorist act".
"Morocco is confronted by the same threats as in May 2003," he said, adding the country would react "with diligence".
The latest attack was the deadliest in the North African monarchy since 33 people were killed by 12 suicide bombers in Casablanca in 2003. An attempted attack in 2007 was thwarted and one of three would-be bombers killed.
Morocco, a country of 32 million people whose economy relies heavily on tourism, has largely been spared the pro-change revolts that have swept the Arab world since the end of last year.
But there have been three protests since February to demand reform, prompting King Mohammed to announce major political changes to increase judicial independence and a greater separation of powers.
In mid-April, he pardoned political prisoners, including Islamists, in a gesture of appeasement.
An official at the Marrakesh prefecture said the blast "could have been the work of a suicide-bomber".
"We found nails in one of the bodies," he said.
Interior Minister Taib Cherkaoui added investigations were underway to identify the perpetrators.
"I cannot say that it was a suicide bomber, but I can assure you that we continue to fight terrorism with all legal means. The criminals implicated in this act will be brought to justice."
He said the bodies of 11 foreigners and three Moroccans as well as 23 wounded had been rushed to Ibn Tofail hospital, the Ibn Sina military hospital and two private clinics.
Among the wounded are 18 foreigners, he added.
"With the help from friendly and neighbouring nations our investigation will determine the circumstances and the perpetrators of this crime," he said.
A senior police official said cordons had been erected at the entrances to Morocco's main cities, "to ensure the internal security of the country".
The Jamaa el-Fna square, listed as a UN cultural heritage site, draws about a million visitors per year. The Argana cafe is popular among foreign tourists, and features in many tourist guides as one of the country's most visited spots.
Britain, Germany and Spain also condemned the attack.
British Foreign Secretary William Hague said he was "shocked and saddened", adding that the attack was "utterly reprehensible".
Hague said initial reports suggesting the blast at the Argana cafe was linked to terrorism were "deeply worrying".
"I am appalled by this explosion," German Foreign Minister Guido Westerwelle said in a statement.
"It was a cynical and abominable act and we condemn it," he said.
Spain, through a foreign ministry statement, expressed "its absolute condemnation of the terrorist attack on Marrakesh".