Guitarist and vocalist Lindsey Buckingham, a former member of the storied rock band Fleetwood Mac, was attacked by a woman when he showed up for an appointment in Santa Monica, multiple law enforcement sources tell NBC4 Investigates.

When Buckingham entered the building, the woman described by authorities as a stalking suspect threw an unknown substance at the two-time Grammy winner and took off. Police have identified the suspect, but no arrests were reported early Wednesday morning.

The woman is known to Buckingham, 76, from past incidents, law enforcement sources said. An arrest is expected soon, they added.

Authorities said they believe the woman found out when and where Buckingham had an appointment and showed up at the location. Buckingham was not injured.

Santa Monica police and the LAPD are working the case.

NBC4 Investigates has reached out to the representative of Buckingham’s for comment.

Born in Palo Alto, Buckingham joined Fleetwood Mac in 1975 and scored hits with “Go Your Own Way,” “Tusk,” and “Big Love.” He won two Grammys with the band, including Album Of The Year for Rumours.

He released a solo album in 1981 and teamed with Fleetwood Mac bandmate Christine McVie for a duet album in 2017.

Buckingham, who shared a complicated personal and professional history with bandmate Stevie Nicks, was dismissed from the band in 2018.