Two car bombs in the northern Lebanese city of Tripoli on Friday killed 42 people and injured hundreds more, raising fears that the civil war raging in neighboring Syria could engulf Lebanon.
Ambulances rushed to the scene as heavy black smoke covered the sky, with television footage showing crushed cars and people carrying bloodied blast victims through the streets.
The blasts went off after Friday prayers near two mosques in the predominantly Sunni port city. A gun battle then broke out between nearby feuding neighborhoods of Jabal Mohsen, which supports Syria's President Bashar al-Assad, and the anti-Assad area Bab al-Tabbaneh.
The blasts come amid rising tension in Lebanon stemming from Syria's civil war, which has sharply polarized the country along sectarian and political lines.
Tripoli has endured clashes between Sunnis and Alawites, the minority sect to which Assad belongs. Lebanon's Shiite Hezbollah movement is a strong ally of the Assad regime.
The first bomb went off near the al-Taqwa Mosque in the city's Abu Ali Square as worshippers were exiting after Friday afternoon prayers.
The second bomb went off outside the al-Salam Mosque in the Mina area.
Sheik Salem Rafei, a Salafi cleric and fierce opponent of Hezbollah, had been praying at al-Taqwa before the blast. His condition is unknown.
Al Jazeera's Zeina Khodr, reporting from Sidon in Lebanon, said that the explosions took place five minutes apart and that ambulances were on the scene.
Attacks have become common in the past few months against Shiite strongholds in Lebanon, particularly after Hezbollah began openly participating in Syria's civil war, but attacks against Sunni strongholds have been rare.
Khodr described Tripoli as "volatile," citing a series of clashes between armed Lebanese groups in the city. The army has been heavily deployed in the area since June 2012.
"This is a volatile city in Lebanon. This is a place which has witnessed clashes between supporters of the Syrian government and opponents of the Syrian government [and] Lebanese factions exchanging fire on many occasions over the past year," she said.
She said the latest attacks were signiicant "because they targeted a Sunni Muslim mosque at a time of heightening sectarian tensions in Lebanon, just a week after a Shiite neighborhood in southern Beirut was hit by a huge explosion.
"So you can imagine how there is a lot of fear. [Residents of Tripoli] are worried. There are reports that there are gunshots being heard in the city. So a very dangerous development at a very volatile time for this country."
Al Jazeera and wire services