The al-Qaeda terror network is among the suspects in connection with a bomb attack that killed 16 in the Moroccan city of Marrakesh, the government said Friday.
Communications minister Khalid Naciri said that investigators would pursue all leads including possible links to Al-Qaeda which operates a North African offshoot active in the region.
"All leads will be investigated, including al-Qaeda," he said.
"The investigation continues to find the perpetrators, but for the moment I am not prepared to point the finger."
Fourteen people, most of them foreigners, died on Thursday when a suspected suicide bomb exploded at a crowded tourist cafe in Djemaa el-Fna, the main square of Marrakesh.
A total of 23 others were badly injured, two of whom died overnight, bringing the toll to 16 Friday.
The blast was condemned as a terrorist attack by the Moroccan government, the United States and France and a Moroccan official said it may have been the work of a suicide bomber.
Interior Minister Taib Cherkaoui said the 14 who died Thursday included 11 foreigners. No nationalities were given for the two fatalities Friday.
Authorities in France said at least six of the dead were French while the Netherlands said a Dutchman had also died.
Israeli media reported that a 30-year-old pregnant Israeli woman and her husband, who was originally from Morocco, were among those killed.
Rabat, Washington and Paris condemned what they said was a "terrorist" attack on the cafe, a favourite haunt for foreign visitors to the touristic city about 350 kilometres (220 miles) south of the capital.
Al-Qaeda's offshoot, Al-Qaeda in the Islamic Maghreb, is active in countries in the region, notably carrying out a series of kidnappings for ransom in recent years.
French President Nicolas Sarkozy, who spoke to Morocco's King Mohammed IV on the telephone Thursday, said the bombing was "heinous, cruel and cowardly."
Witnesses said the explosion happened on the terrace of the popular Argana cafe, whose facade and first floor were severely damaged, with tables and chairs strewn around the terrace.
Moroccan newspapers united in condemning the attack, coverage of which dominated front pages.
"The explosion was so powerful that it was heard several kilometres (miles) from the Argana cafe," wrote the independent Arabic daily Al-Massae.
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.
Major Moroccan Islamist movement Justice and Charity condemned the "barbaric" attack and appealed to the authorities "not to repeat the human rights abuses" that followed the Casablanca attacks.
Morocco depends heavily on tourism, with around 9.4 million tourists visiting the country in 2010, two million of them French.
The country of 30 million 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, including greater judicial independence.
In mid-April, he pardoned political prisoners, including Islamists, in a gesture of appeasement.
Moroccan security forces have been deployed in the country in the wake of the blast.
A senior police official said cordons have been erected at the entrances to Morocco's main cities, "to ensure the internal security of the country".
French intelligence and anti-terrorism experts will travel to Marrakesh on Friday to help in the probe, a source said.
International police agency Interpol condemned the attack and said it would ensure "the Moroccan authorities investigating this terrible attack have the full support of the global law enforcement community."
The United Nations, Britain, Germany, Spain and the Council of Europe human rights watchdog also condemned the attack.
British Foreign Secretary William Hague described it as "utterly reprehensible, and said alleged links to terrorism were worrying.