After people called to report hearing explosions, emergency officials initially thought there had been underground methane gas blasts. But it turns out that New Hampshire actually had three small earthquakes over the weekend.

The tremors caused no damage or injuries.

The state Emergency Management Agency said the quakes were felt Saturday night and Sunday afternoon in the Portsmouth-Exeter area of the northeastern U.S. state.

The U.S. Geological Survey listed two of the quakes as magnitudes 1.4 and 1.9. A magnitude for the third quake was not available.

Initially, officials investigated whether the sounds and tremors were caused by underground methane gas explosions, and the naturally occurring gas was found escaping from the ground in Portsmouth on Saturday.

However, authorities were able to rule that out as the cause, Assistant Fire Chief Steven Achilles said. He said the methane gas discovery was either a coincidence or a result of the tremors.

New Hampshire experiences an average of three to four earthquakes per year, most of them so minor they are not even felt, said Jim Van Dongen, spokesman for the state Office of Emergency Management.