The man's sign was attached to a rope, which appeared before he stepped onto the sign Tuesday at about 5 p.m.
Part of the southbound I-805 was closed Tuesday evening due to a man sitting on the freeway sign above the bridge, CHP authorities said.
The southbound lanes between I-5 and Balboa Ave. were closed starting at about 5:20 p.m., and traffic will be diverted off by CHP officers.
Just before 7 p.m., Caltrans announced the long-term closure of all lanes of the southbound I-805 and of the northbound I-805 off-ramp to westbound Balboa.
The San Diego Police Department's emergency negotiation team assisted CHP, police and fire rescue personnel. They struggled for hours to talk the man down from the freeway sign.
Just after 1 a.m. the unidentified man was taken into custody without incident.
At times during the standoff, the man appeared to be trying to hold up a sign. Later he could be seen writing more words on the sign.
He will be given a mental health evaluation at a nearby hospital officials said.
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