An Egyptian policeman shot and killed a Cairo street vendor on Tuesday after an argument over the cost of a cup of tea, the interior ministry said.

A security official said the officer involved was arrested after dozens of bystanders protested at the scene of the shooting in an eastern suburb of the capital, chanting: ‘The police are thugs.’

‘During a police patrol a dispute broke out between the officer and the seller over the price,’ the ministry said in a statement.

‘The policeman opened fire, killing the vendor and wounding two passers-by.’

Egypt's police have been on the defensive after rights groups denounced alleged torture and deaths in detention, as well as arbitrary arrests and the disappearances of government opponents.

The alleged abuses are reminiscent for many Egyptians of those perpetrated by police under the rule of longtime president Hosni Mubarak, who was toppled in 2011 partly as a result of public outrage to impunity for security services.

A court this month sentenced a policeman to life in prison for shooting dead a taxi driver over a fare dispute.

President Abdel Fattah al-Sisi had said he would ask parliament to amend the law to toughen sanctions for police abuses after the February killing.

Thousands of doctors held a protest earlier this year against the police after officers allegedly assaulted two doctors in a hospital.

And several policeman have been detained for violence against prisoners and some have been sentenced to jail in the past year.