Azizabad police on Tuesday arrested the main suspect in the murder of a 15-year-old Afghan boy.

Noor Agha had been shot dead on Sunday, allegedly by an apartment-owner in Karachi's Karimabad area, after he asked for Rs25 for cleaning a staircase.

Superintendent Police (SP) Gulberg Bashir Brohi told Dawn that the suspect was arrested while he was reportedly trying to flee the country on a US-bound flight.

The suspect was carrying a large amount of Pakistani and foreign currency, he added.

The officer said Noor was a scavenger of Afghan origin who, along with his brother Umer and others — all residents of the Machar Colony near Sohrab Goth — collected garbage from localities in Karimabad for a few rupees per family.

On Sunday, Noor and his colleague, Naimat, had washed the staircase of a flat owned by Ayaz Malik and demanded Rs25 for their services.

Instead, the suspect retrieved his pistol from his apartment and allegedly shot the boy before fleeing the crime scene.