A convicted bank robber booked into jail Monday following two downtown bank holdups is being investigated in at least 15 heists nationwide.

Police arrested John Daniel Stolarz, 47, Reno, Nev., as he walked out of the Temple Square Hotel, 75 W. South Temple, about 11 a.m. He was later booked into the Salt Lake County Jail.

The arrest occurred about a half-hour after Zions Bank, 102 S. Main, and Citibank, 2 S. Main, were robbed by a man carrying a briefcase and claiming to have a bomb.

Stolarz, who was paroled in February from a federal prison after serving eight years for bank robbery, is also being questioned in connection with a robbery earlier this year of Deseret Federal Savings, 54 S. Main, and about a dozen other bank holdups committed between New York and Las Vegas, said FBI agent Bob Lund.