NEW YORK (AP) _ Technical problems caused by a worker's error disrupted the Nasdaq Stock Market Friday, delaying final prices and the compilation of Wall Street's major indexes.

The problems with two key trading systems forced the Nasdaq to extend its regular trading session by an hour to 5 p.m. EDT and cancel the late trading session it regularly holds.

Officials of the computerized stock market said an error by an MCI Worldcom technician led to the problems.

``This was unrelated to system capacity'' or other problems at the Nasdaq, spokesman Scott Peterson said. ``Human beings make mistakes.''

It was the second straight day of trading problems for the Nasdaq, but Peterson stressed that Thursday's glitches were unrelated to Friday's troubles.