At least 16 people have been killed in a bomb explosion in Sri Lanka's capital, Colombo, the military says.
There are fears that the death toll could rise further
At least 37 were also injured in the blast, which hit the city's busy Nugegoda district.
The bomb went off outside a clothing shop, after a guard reportedly tried to open a suspicious parcel.
The blast came just hours after a suicide bomber killed one person and hurt two in Colombo. Officials blamed the two attacks on Tamil Tiger rebels.
They took place a day after Tamil Tiger leader Velupillai Prabhakaran described hopes for peace as naive, after increased fighting in the north.
The Tigers say that more than 20 civilians, most of them children, were killed in two attacks by the military in the north on Tuesday.
The second blast occurred just outside the four-storey clothing shop during the evening rush hour.
Army spokesman Brig Udaya Nanayakkara said the explosion occurred after a security guard at the complex spotted a suspicious parcel and tried to handle it.
A bus caught fire as a result of the explosion, the defence ministry said.
There are fears that the death toll could rise further. Police are currently searching rubble for more bodies.
Mangled and charred motorcycle and taxi parts were scattered nearby.
"I was on the top floor of a shoe shop with my wife and child when I heard a big blast and there were glass pieces all over us," local resident A Jayasena told the Associated Press.
Recent rebel attacks on civilian targets of this scale have been rare, but bombings causing mass casualties have been a feature of Sri Lanka's conflict in the past.
Sri Lankan troops were deployed at the ministry after the first blast
In the first attack, a suicide bomber blew herself up outside the offices of Welfare Minister Douglas Devananda, who escaped unharmed, officials said.
He is the leader of a rival Tamil movement, the Eelam People's Democratic Party.
BBC South Asia correspondent Chris Morris says Mr Devananda is a bitter opponent of the Tigers and has been targeted by them before.
Mr Devananda's personal secretary and two security staff were injured by the explosion. The secretary later died in hospital.
Officials said the suicide bomber was a disabled woman who mingled with crowds outside the government building before detonating her device.
The Tamil Tigers said that at least 11 of those killed in the north on Tuesday were schoolchildren whose bus hit a mine laid by the military. The army denied responsibility.
Nine others died when the Tigers' radio station was bombed, the rebels said.
In a broadcast speech, Prabhakaran said it was naive to believe peace was possible with any of the parties in the Sinhalese-dominated south.
Since his last address the Tigers have been driven from the east of the country and are under pressure in areas of the north that they still control.
A Norwegian-brokered ceasefire in 2002 broke down two years ago, resulting in renewed fighting that has killed more than 5,000 people.
At least 70,000 people have died since the war began in 1983.