SUEZ, Jan 6 (Aswat Masriya) – Egypt's top prosecutor ordered the arrest of two police officers who shot dead two brothers after refusing to stop at a security checkpoint in Suez on Monday.

Prosecutor General Hisham Barakat ordered the officers' arrest for four days pending investigation.

The officers told the prosecution that the shooting was not intentional. They said they were shooting into the air; the bullets hit the victims "by mistake".

Suez Security Director Tarek al-Gazzar told Aswat Masriya on Monday that the two killed men were driving an unlicensed motorbike, which aroused suspicion among security forces at the checkpoint. The men sped away when an officer asked them to stop, Gazzar said, prompting the officer to fire at them. 

The Suez Prosecution ordered an autopsy for the killed men to determine the cause of death. It also ordered the seizure of the projectiles used in shooting at them.

Families of the two brothers gathered outside the morgue where their bodies were kept late Monday, chanting against the security director and the ministry of interior. Security forces fired teargas to disperse them when they marched to the vicinity of the governorate's security headquarters.

The incident shortly follows the shooting of a driver who refused to stop at a Sinai checkpoint on Friday. Security forces in North Sinai shot at a car which refused to stop at a checkpoint in al-Arish, killing the driver and injuring another passenger.

Army Spokesman Mohamed Samir said in a statement the car was trying to flee the checkpoint, refusing to respond to army forces' warning signs. He added that the car is owned by someone other than the two passengers and that killed driver possessed no documents giving him the right to drive it.

Egyptian authorities have intensified security measures in the Sinai Peninsula in reaction to proliferating militant attacks there, particularly since the army's ouster of Islamist President Mohamed Mursi in July 2013, which followed mass protests against his rule.