Vendor accused of killing man in Tahrir Square over price of drink

A street vendor has allegedly stabbed and killed an unemployed man in Tahrir Square in a row over the price of a drink.
Passers-by captured the vendor and handed him over to the police.
They said the vendor pulled the man with one hand and stabbed him in the neck with the other before trying to escape. 
The 30-year-old vendor was accused of possessing drugs.
Prosecutors are investigating the incident.
Edited translation from Al-Masry Al-Youm