Mexico-California border cities shaken after quake

Hundreds of people camped out overnight as smaller tremors shook buildings with cracked floors, walls and broken windows.

"I wasn't going to put my family at risk. Lots of homes have cracks," said Fermin Garcia, a teacher who slept with her family in a tent pitched between two shopping centers.

Broken gas pipes sparked a number of fires on Sunday, and darkened streets in Mexicali triggered car accidents, but no major buildings appeared to have collapsed.

Power was slowly being reestablished on Monday, but many state-run hospitals lacked power and patients were laid out on beds in parking lots due to worries over cracked walls.

A highway connecting Mexicali with the nearby border city of Tijuana on the Pacific coast was ruptured by a crack at least a meter (3 feet) deep, according to a Reuters witness.

A liquefied natural gas import terminal operated by Sempra Energy south of Tijuana was not damaged however, a company spokeswoman said