A second earthquake, this time of magnitude 7.1 on the Richter Scale, rattled parts of Southern California on Friday evening. Reportedly the biggest tremor to strike the US state in two decades, the quake touched off fires, damaged buildings, and forced the evacuation of a hospital in a desert town North East of Los Angeles.

The epicentre of the earthquake was at Ridgecrest, about 240 km from Los Angeles. The 6.4-magnitude earthquake of Thursday had originated at the same spot.

Tremors were felt Los Angeles, San Diego, Las Vegas and many other areas in the state. According to reports, this is part of a sequence – California has felt over 20 quakes in the 36 hours leading up to Friday.

A viral video shows the moment news anchors live on-air felt the quake. “If you’ll give us a brief moment here, we’re making sure that nothing is going to come down in the studio here,” the woman anchor says.

“We’ve got fires, we’ve got gas leaks, we’ve got injuries, we’ve got people without power,” Ridgecrest Mayor Peggy Breeden told Reuters. California Governor Gavin Newsom approved an emergency proclamation.

Basketball and baseball games were interrupted as stadiums-full of people felt the tremor and rushed from their seats. Players however apparently did not feel the quake and continued with their game.

The effect of the earthquake was the worst in Ridgecrest with scary videos of super-markets losing electricity, their shelves rattling as products fall out became viral online.

About 1,800 people had no power after the quake, Kern County Fire Department chief David Witt told the BBC. However, civilians suffered only minor injuries and there was no significant damage to property.

California lies on a number of faults – regions where the earth’s tectonic plates come together – and thus is prone to earthquakes. The largest, San Andreas Fault extending about 1,200 km through the state.

According to seismologists quoted by American news organisations, the fault is growing and may create potentially hazardous situations.