We're told the men surrounded Williams and his crew -- and even the suspects did not brandish a weapon, it was clear they wanted cash ... or else.
Williams and his guests complied. Our law enforcement sources tell us the suspects got around $1,000 in cash and then fled the scene.
Cops were called but so far, they have not located the men. We're told the LAPD is investigating and looking for possible surveillance footage. The suspects have been described as 3 African-American men.
A rep for Williams tells TMZ Sports ... the NFL player is doing okay.
Williams was a stud for the Chiefs in 2019 -- but REALLY broke out during the playoffs.
During Super Bowl LIV, he rushed for 104 yards and a TD against the SF 49ers -- and also caught 4 passes for 29 yards and a TD!
The receiving TD with 1:12 left in the game basically sealed the victory for KC.
Some people feel he could have been named Super Bowl MVP.
Unclear why Williams was in L.A. -- but he was born and raised in San Diego which is only a 3-hour drive away.