San Francisco, March 25 (IANS) Graffiti referencing to the March 15 Christchurch attacks that killed 50 Muslim worshippers, was discovered at a California mosque after a possible arson, authorities said.

The fire started at around 3.30 a.m. on Sunday at the Dar Ul Arqam mosque.

Escondido Police Department Lt. Chris Lick has not revealed what the graffiti said, but said that local and federal authorities were investigating the incident as a hate crime, NBC News reported.

No suspects had been identified, while one person was injured, Lick said.

He added that worshippers staying at the mosque overnight extinguished the blaze, which caused minor damage to the building's facade.

A member of the local Muslim community, Yusef Miller, told NBC that the fire and graffiti has left worshippers on edge.

The Dar Ul Arqam mosque opened four years ago.

The Christchurch attack was carried out by a lone gunman at two mosques.