Emergency services were called to the scene and spent over four hours containing the fire, which destroyed the dome of the mosque. He found no alarm active and that the doors to the mosque were unlocked.
TIME also has reported that Hashmi has already received several offers of temporary worship sites until the centre can be rebuilt.
Watching the destruction of his community's prayer home, AP quoted Hashmi as saying, "It's sad to stand there and watch it collapse down".
According to the Victoria Advocate, the cause of the fire remains undetermined but is being investigated.
Photos of the mosque show the dome topped, and and the center's president Shahid said: 'It looks completely destroyed'.
Speaking to Al Jazeera, Mr Hashmi said he hoped the act had not been a hate crime, but said the outpouring of support and donations had been "incredible".
A GoFundMe page has so far collected $165,677 (£131,000) in donations to help the congregation rebuild the mosque, Mail Online reported. "Based on rough engineering estimates and the original cost of construction, we've revised the to be closer to amount it's going to cost to rebuild the mosque".
The mosque has been the target of vandalism before.
'Because of growing anti-Muslim bigotry in our nation, and because of the recent spike in hate incidents targeting Islamic institutions and individuals, we urge investigators to keep the possibility of a bias motive for this fire in mind, ' CAIR-Houston Executive Director Mustafaa Carroll said.
Trump signed the executive order on Friday barring citizens of Iraq, Iran, Syria, Somalia, Sudan, Libya and Yemen from entering the United States for the next 90 days, and suspending admission of all refugees for 120 days. They can not return to the US for 90 days.
The decision did not strike down the executive order, and is only temporary.