Two terror strikes within two hours shook Lahore and Karachi on Tuesday despite a heightened security alert on account of Chehlum, leaving 15 people dead and wounding more than 70.

A teenager blew himself up in Lahore near a Chehlum procession, killing 11 people. The Pakistani Taliban claimed responsibility for the attack, saying they had targeted police.

About 90 minutes later, a motorcycle bomb went off in Karachi's Malir, killing four people, including three policemen.

The Lahore bombing took place near the Urdu Bazar when a teenager tried to join a Chehlum procession before detonating close to a police checkpoint.

“The bomber had strapped bombs to his body as well as carrying explosives in a bag,” the city's police chief said. “He tried to sneak into the procession and exploded himself when police stopped him for a body search at an outer checkpoint.”

An hour and a half later, a second attack hit Karachi.

“It was a suicide bombing. The bomber was riding a motorbike and carrying a bag in his hand, which had explosives in it. He struck one of our police mobile vans. The police were the target,” a senior police official said.