Three days mourning announced after bombing in Karachi
The Pakistani city of Karachi is in mourning after a powerful bomb ripped through a mainly Shia Muslim area, killing at least 45 people.
Schools and businesses are closed after a strike was called to protest against the attack in Abbas Town.
Although, no group has yet said it planted the bomb, which went off near a mosque as worshippers left evening prayers but suspicion is likely to fall on Sunni militant groups.
They are thought to have set up several training camps for militants, and police seizures have shown they have access to large quantities of weapons and explosives.
Pakistan's Shia minority are the target of frequent sectarian attacks from Sunni militant groups.
Sunday night's explosion destroyed several buildings and set others on fire, sending a huge column of smoke into the sky and causing a power cut in part of the city.
Police are investigating whether it was a suicide attack and some reports have spoken of a second explosion.
“At least 150 people were wounded by the blast”, police say.
Monday's strike, being observed in several cities across Sindh province, was called by an alliance of political groups.
Public transport stayed off the roads and petrol pumps and filling stations were also closed.
Three days of mourning have also been announced by Shia groups.
Some relatives and local residents were still sorting through the rubble on Monday morning.
One of them, Farzana Azfar says, "I am here to look for my relative. People said he was here but they have no idea about him. It appears that some bodies are still in the rubble."
Pakistan's main political and religious leaders have condemned the attack, the latest to target the Shia minority.
Karachi, Pakistan's biggest city and commercial capital, has a long history of violence.
Some activists called 2012 the worst year in living memory for attacks on Pakistan's Shia community, with rights groups estimating that about 400 perished in militant attacks.
But this year is also shaping up to be among the deadliest, nearly 200 people were killed in two separate bombings targeting Shias in the south-western city of Quetta in January and February.
Last month Pakistan's Supreme Court called on the authorities to devise a strategy to protect Shia Muslims more effectively, given the increase in attacks.