The winning numbers — 2, 4, 23, 38, 46 with Mega Ball 23 — were announced here at 11:00 pm (0300 GMT Saturday).
There has been no official announcement from Mega Millions lottery yet.
MSNBC television cited an unnamed Maryland lottery official in reporting the news. The Washington Post, using similar sources, said the winning ticket had been sold in Baltimore County.
The winner has not claimed the prize yet.