Lorna Roxanne Green, 22, had pleaded not guilty to a single charge in connection with a fire in May last year at Wellspring Health Access, which was being built in Casper.

The clinic, whose opening was delayed by several weeks because of damage, is the only clinic to offer surgical abortions in conservative Wyoming.

Abortion remains legal in the state, but it is one of several where conservative lawmakers are trying to restrict it.

Investigators say Green poured gasoline around the facility after breaking a window there.

She was identified by tipsters after a US$10,000 reward was offered.

Oil City News, a Casper-based outlet, reported that Green will stand trial on July 24.

Media reports have previously said Green admitted the attack, and told investigators she was motivated by her opposition to abortion.

Despite majority public support for abortion, conservative politicians and their evangelical grassroots supporters have made inroads in recent months into restricting access to the procedure in several parts of the US.

Last year the nation’s supreme court overturned a decades old ruling that had enshrined a woman’s right to an abortion.