— New York City's Board of Elections reported scattered problems at polling sites during Tuesday's primary election for mayor and other offices.

Board spokeswoman Valerie Vazquez said voting issues were isolated. The city was forced to use old-fashioned lever-style voting machines Tuesday instead of the paper ballot system that have been in use since 2010.

Several voters reported that the lever machines weren't working at their polling sites and paper ballots had to be used after all.

One voter in Manhattan's East Village said workers at her polling place handed out paper ballots because of what they described as a computer glitch.

The voter, Stephanie Forman, said poll workers did not know when the problem would be fixed.

The lever machines were used for decades but the city switched to optical scanners reading paper ballots in 2010 to comply with federal law.

The lever machines returned because of logistical issues with getting the scanners ready for use on Tuesday and then again in three weeks for a possible Oct. 1 runoff. A runoff is likely in the heavily contested Democratic mayoral primary, where a candidate must capture 40 percent of the vote to avoid one.

A leader of a good-government group said he's concerned that widespread use of paper ballots could delay the results of the primary.

"If there are an extraordinary number of paper ballots, it will be difficult to know who places first and second in a close election among the top three candidates," said Dick Dadey, executive director of the Citizens Union.

The Board of Elections said most problems Tuesday concerned voting machines in Queens and Brooklyn and some in Manhattan.

The board directed voters to report problems to its Twitter feed.