Security at Legacy Salmon Creek in Vancouver is closely monitoring who is going in and out of the building Monday night.
The Clark County Sheriff's Office said deputies were alerted to a possible threat about a person at the hospital at 5:30 p.m.
A man claimed he was going to bring a semi-automatic gun to the hospital, according to deputies.
Investigators believe it's a domestic violence situation.
A hospital representative said the building was not put on lockdown Monday night.
Deputies still stationed themselves at the hospital, in case the man who made the threat showed up.
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