A man charged over a car explosion that damaged the Australian Christian Lobby offices in Canberra's south told police he was "sorry about the mess", court documents said.
The Kambah man, 36, will fight charges of arson and property damage on mental health grounds after he allegedly blew up a car packed with gas cylinders and seriously injured himself in December 2016.
The man suffered serious burns in the late-night explosion. He was flown to Sydney for treatment a day after police said he had walked five kilometres to Canberra Hospital after the incident.
The ACT Policing investigation was delayed while the man was treated for serious burns and a mental health condition. He was charged in April.
The man faced the ACT Magistrates Court over the incident for the first time on Wednesday, when he was committed to stand trial in the higher court.
His lawyer, Peter Woodhouse, of Ben Aulich and Associates, had previously indicated he would plead not guilty due to mental impairment.
Mr Woodhouse said the facts of the incident were not in dispute but there was an issue of mental health.
Court documents said police were called to the Campion Street building after reports of a car fire and found the van, parked about one metre from the building, in flames about 9.30pm on December 21.
Police seized the destroyed vehicle, four gas bottles and charred papers.
The building's facade and windows were burnt and there was smoke damage to the inside walls, carpet and singed window coverings.
A man, who police believe was the accused, was captured on CCTV footage as he walked along a nearby street with his arms outstretched about 10.30pm.
When the man arrived at the hospital's emergency room, staff noticed his hair, face and arms had been badly burned and were blistering.
The man allegedly hired the van from a car rental service at Canberra Airport the previous day, before he drove to a Phillip supermarket and spent $140 on four 8.5 litre gas bottles.
In an interview with police the night of the explosion, the man allegedly said he had intended to harm himself. He chose the building as he disliked the ACL because "religions are failed", the documents said.
He ended the police interview by saying: "Sorry about the mess."
Police later searched the Deakin unit he was living in and found a framed print of Buddha smashed on the floor and gas cylinder tags.
In the months leading up to the explosion, he allegedly searched the internet for "how to make ammonium nitrate", "pressure cooker bomb", "c4" and "how much gas leak to cause explosion".
His mobile phone also allegedly showed internet searches for "china lgbtq", "israel same sex marriage", "hinduism same sex marriage" and "countries with same sex marriage".
In November, he'd searched "Australian Christian Lobby".
He allegedly told medical staff he had driven a van up to a "church", opened four gas cylinders and lit a lighter. After they ignited, he had walked to the hospital.
The man said he was "not a huge fan" of the lobby or religion due to their views on sexuality, but said his decision to drive to the building was "spontaneous" because he couldn't find another suitable location, court documents said.
ACT Policing previously said there was no political, religious or ideological motivation behind the explosion after officers interviewed the accused.
The man is on bail. His case returns to court on August 24.
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