Two men who were denied entry to a nightclub later returned with others and firebombed it early Friday, setting off a blaze that killed all 16 people who were trapped inside by the smoke and flames, authorities said.

Terrorism was quickly ruled out as the cause of the attack at the El Sayad restaurant and club in Cairo's Agouza district.

Police were searching for six people suspected in the attack, which occurred after two of them were not allowed to enter the club, said Interior Ministry spokesman Abu Bakr Abdel-Karim.

After the two were refused entry, they "went and drank alcohol somewhere else," then brought four others with them, arriving on three motorcycles about 6 a.m., Abdel-Karim said. "They then threw a Molotov cocktail at the entrance of the place." No one who was inside the club survived, Abdel-Karim said. - AP