Several religious leaders and members of law enforcement attended prayer services the day after the fire.
"It is the responsibility of everybody in this city and county to make sure that we respect each other's faith and houses of worship," said Bishop James Dixon, the head pastor of The Community of Faith Church. "None of us can prosper while the other does not. None of us can feel safe while the other is in fear."
Investigators say they have no new information about who sprayed a flammable liquid on the front door and set it on fire.
A caretaker who lives in a house behind the mosque heard the fire alarms ringing.
He was able to put out any flames before it destroyed the building, but he did not see who set the fire.
"You know, this is a benefit to the community, and when someone tries to destroy that, it's very sad," said Rachel Moreno with the Harris County Fire Marshal's Office.
Four tires were also slashed on a vehicle belonging to the mosque's imam. It was the only car in the parking lot that was vandalized.
"As a community, we hold no ill will towards anybody who was behind this," said M.J. Kahn, the president of the Islamic Society of Greater Houston. "We just pray to Lord Almighty that they do come forward because we don't want these kinds of incidents to be repeated again."
Detectives don't know yet if this was a simple prank or a hate crime.
"Hate crimes are message crimes, so we must send through what we are doing here today an unequivocal message that such crimes will not be allowed in this richly diverse community of ours,' said Dayan Gross with the Anti-Defamation League.
"If somebody could come forward, because today it's this mosque, tomorrow it's somebody else's church or their home, so that person needs to be dealt with," said Harris County Sheriff Ed Gonzalez.
If you have any information, you're asked to call Crime Stoppers at 713-222-TIPS.
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