Guitarist Frankie Sullivan -- a founding member of the band Survivor -- had his L.A. home burglarized ... and cops say the thieves made off with fancy watches worth a ton of dough.
Law enforcement tells TMZ ... burglars smashed their way through the window at the "Eye of the Tiger" guitarist's San Fernando Valley home in the hills earlier this month, taking a bunch of timepieces, worth more than $300,000.
Cops think it was the work of a South American burglary crew that flies into the country to hit expensive homes -- several belonging to celebs -- and they allegedly use fire roads in the mountains to access the luxury properties.
Law enforcement is urging folks to put trail cams around their property, make sure the area is well-lit ... and put alarms on sliding glass doors and second-story windows. They say that's how the burglars are getting into the homes.
As we reported, Keanu Reeves' home was raided earlier this month, too ... and law enforcement sources now tell us the gun stolen from his property was a Glock pistol.
We also learned the home of Leonardo DiCaprio's neighbor -- who lives in the same area as Keanu -- was also broken into that same night, with more than $100k in jewelry getting snatched. Police think that the break-in is connected to Keanu's.