CHICAGO (CBS) — A far north suburban community was in shock Wednesday morning, after fire destroyed their place of worship.

The Illinois State Fire Marshall and the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives was investigating the cause of the extra-alarm blaze at the Guru Nanak Sikh Mission in Island Lake.

A worship service ended just 90 minutes before the fire started around 8:30 p.m. Tuesday.

Fire crews were forced to fight the flames from outside the temple, due to dangerous conditions inside.

Investigators said the fire started in the lower level, and spread inside the walls and floors of the building. Flames and smoke were spewing from the roof when the first firefighters arrived, and the fire was quickly upgraded to a two-alarm fire, to bring in extra crews.

“Initially we’re on an offensive mode. So, in other words, we had companies operating in the building. The fire had migrated from floor to floor,” Wauconda Fire Chief David Dato said.

No one was inside the temple at the time of the fire, but the building was a total loss.

Pastor Baba Daljit Singh said the mission had about 500 members at last check. Singh founded the church in 1998. He said he’s heartbroken by the loss.

“It’s very sad news, because of our religious stuff is here,” he said. “I feel I am burning inside. … I don’t want to say anything else more. I have no words, because I am feeling it’s not burning; I am burning inside.”

According to the Daily Herald, the mission was cited for multiple building code violations, dating back to 2011 – including having no working fire alarm system.

Agents with the ATF were brought in to assist with the investigation, as is standard protocol for any religious-affiliated fire.