A 23-year-old man has been charged with a hate crime after a mosque in California was reportedly “firebombed” with people inside, prompting renewed focus on how such incidents are reported.

The incident occurred during Friday prayers at the Islamic Society of Coachella Valley, around 75 miles away from the scene of the San Bernardino shootings last week.

Carl James Dial Jr was arrested later on Friday and faces charges of arson, a hate crime and burglary, police said. In an interview with NBC News, his parents were quoted as calling him a “loner” and stressing that he was innocent until proven guilty.

No one was hurt in the alleged attack on the mosque, which local mayor Steven Hernandez described as “a cowardly act of vandalism”.

But people questioned the way the incident was reported and asked whether, if confirmed, it should not be treated as a suspected incident of white terrorism.

According to a statement from Riverside County sheriff's spokesman Captain Andrew Shouse, the fire on Friday was contained to the small building's front lobby.

Reymundo Nour, the mosque's acting imam, told the Associated Press people at the mosque described hearing a "loud boom" and seeing flames.