“Around 6.30 am, six thugs returned with three motorcycles and attacked the shop with guns and molotov cocktails.”
Mr Hassan said that all the victims were employees of the nightclub: 11 men and 5 women.
But MENA, Egypt’s state-run news agency, quoted an unnamed security official as saying it was three men on a motorcycle who threw Molotov cocktails into the club and then fled.
Police were looking for two young men who carried out the attack in the Agouza district because they were previously not allowed to enter the club, MENA reported.
While Egypt is regularly hit by extremist violence, particularly targeting security forces, attacks on nightclubs are rare.
The agency said the fire was quickly extinguished and security authorities are investigating the attack. Security officials earlier said 18 people died.
Online video posted by newspaper Youm 7 showed thick black smoke pouring through the doorway of the el-Sayad restaurant as onlookers milled outside unable to help. Flames were burning the inside of the building and charring the facade.
The wood entrance of nightclub is believed to have contributed to the speed of the spread of fire. Some reports said that the attackers threw gasoline at the entrance of the nightclub, which is located in the ground floor, few steps under ground, to block those inside from escaping.
Mr Hassan said that the police arrested one of the perpetrators and claimed that the group had attacked another nightclub before but they were not arrested.
A witness working in a shop nearby said that he heard gunfire in the early morning. “I saw two people in a motorcycle covering their face.”
“I saw some of the dead people while they were taken by the ambulance, they are not burnt, they most probably died because of suffocation.” Mohamed Ali said.
The interior ministry denied that the incident was terrorism. Security officials told the press that the preliminary investigation confirmed that the attack happened after a dispute between the nightclub staff and some other people, who then threw Molotov cocktails at the entrance.
Islamist militants have claimed a number of bombing and shooting attacks in Egypt, mostly against members of the security forces since the army toppled Mohamed Morsi, the former president, of the Muslim Brotherhood in 2013 after mass protests.
A timeline of Mohammed Morsi’s downfall and the aftermath
It has been nearly two years since Mohammed Morsi was removed from power and the crackdown on the Muslim Brotherhood
July 3, 2013
Mohammed Morsi is removed from power
Morsi is deposed and detained by the military. Supporters of the ousted president begin mass sit-ins demanding that he is reinstated. Brotherhood figures are arrested by the military.
July 27
Pro-Morsi sit-ins continue
Pro-Morsi sit-ins and daily demonstrations continue. Security forces clash with protesters leaving 80 dead at the two major camps.
August 11
Egyptian government cracks down on sit-ins
The Egyptian government declares it will remove the sit-ins within 24 hours.
August 14
Protesters removed by force
Security forces take action against the protesters, using armoured vehicles and bulldozers, in the deadliest massacre of Egypt’s modern history. An estimated 1,000 people are killed across the two major camps.
October 6
Further demonstrations leave 51 dead
Police mount deadly attack on pro-Morsi protest in Cairo, killing 51 demonstrators.
November 4, 2013
Morsi in first court appearance
Morsi appears in court for the first time, charged in connection to deadly violence outside his Cairo palace in December 2012.
November 4
Morsi in first court appearance
Morsi appears in court for the first time, charged in connection to deadly violence outside his Cairo palace in December 2012.
November 24
‘Unofficial’ protests criminalised
In an example of the government’s increased crackdown, ‘unofficial’ protests criminalised
December 24
Jihadist group kills security personnel
At least 12 security personnel killed as deadly blasts rock a Nile Delta security directorate. The attack is later claimed by Ansar Bayt el Maqdis, a jihadist group.
December 25
Muslim Brother blacklisted
The Muslim Brotherhood are blacklisted as a terrorist organisation.
January 24, 2014
Cairo hit by quadruple bombing, later claimed by new militant group Ajnad Misr.
January 25
Third anniversary of the revolution ends with protesters killed
At least 49 people killed as police crush protests with deadly force on the third anniversary of Egypt’s revolution.
January 24, 2015
Leftist poet killed by police
Police shoot dead leftist poet in central Cairo on the eve of the revolution’s fourth anniversary. Her death prompts rare criticism in the state media.
March 5, 2015
Mohamed Ibrahim, the interior minister, is sacked. He had overseen the bloodiest and most repressive eras in Egypt’s modern history.
April 21, 2015
Morsi is sentenced to 20 years in prison.