Six people have died and at least 20 people have been injured in two bomb blasts in the Pakistani city of Lahore, police say.
The second blast was more powerful than the first
Many of the injured are in critical condition and doctors fear the death toll may rise.
No-one has claimed responsibility for the attacks.
Police say the blasts were not targeted against a particular person or community, but were aimed at creating panic in the country.
A home-made explosive device fitted to a bicycle exploded on Thursday morning near the inter-city bus terminal and just outside a busy public park.
One passer-by was killed instantly and several others injured in the blast which police say was triggered by a timing device.
A second, more powerful, explosion occurred an hour later in the commercial area of Icchra.
Two people died immediately in the explosion and three others died later in hospital.
Authorities have not blamed any particular group for the blast, but they say similar tactics were used to detonate both bombs.
Senior Superintendent of Police in Lahore Chaudhry Shafqaat Ahmad told Reuters: "The two blasts look quite similar to each other, and we fear that there may be more blasts."
Shopkeeper Mohammed Aslam, an eyewitness at the second blast, said "Something exploded with a big bang."
"People were running for help and at the site of the blast, I saw many injured people who were bleeding. I saw blood, flesh and dust everywhere," he told Associated Press.
Four people have been arrested in the last two weeks for possessing explosive materials near inter-city bus terminals in two towns in Punjab province.
But it is not clear whether these arrests were linked to the group that carried out Thursday's attacks.