A double car bombing and a mortar strike targeted pro-government areas Tuesday in two of Syria's largest cities, killing at least 54 a day after President Bashar al-Assad declared his candidacy for reelection.

The attacks in Damascus and Homs heightened fears of an escalation ahead of the June 3 vote and showed that despite a series of battlefield defeats, the rebels remain capable of hitting the government and its core of support.

A car bombing in Homs left at least 40 dead and 116 wounded, the official SANA news agency said. In Damascus, mortar shells slammed into a school, killing 14 and wounding 86, the state news agency reported. The Britain-based Syrian Observatory for Human Rights said 19 were killed, including 14 children. - AP