SAN JUAN, Texas – A man holding a campaign sign outside of a polling station in South Texas was shoot in the leg Tuesday in an apparent drive-by shooting, but authorities hadn't identified any suspects or determined whether the motive was political.

San Juan police Chief Juan Gonzalez said he was withholding the identity of the 55-year-old victim until the man's family could be notified. The injury was not life-threatening, and Gonzalez said he expected the man to be released later Tuesday.

"I think it's very unfortunate it happens here when people are exercising their right to vote," Gonzalez said. "One of the main things that we're doing is for the rest of the day we have placed an officer there to make sure citizens feel safe and they're not intimidated or fear coming to vote."

The shooting on primary day in Texas happened on a busy street corner packed with workers and signs. Hidalgo County officials said in a statement that the shooting did not interrupt voting and hoped "this isolated incident does not discourage voters from participating in the electoral process."

The man had just started working that morning for the campaign of Hector "JoJo" Mendez, a candidate for Hidalgo County constable. Mendez, reached later by phone, said the man approached him Friday about some campaign work.

"I don't know if they're trying to intimidate me but it's not going to work," Mendez said. Neither Mendez nor Gonzalez said they had any evidence that the shooter was targeting a particular campaign or candidate.

The only lead so far was that a witness saw the passenger-side window of a red pickup lower as it passed. But the witness didn't see the shot, Gonzalez said. Police were canvassing the area looking for surveillance video that may have captured the incident.

The worker was standing near the curb of a busy road holding a Mendez sign. About two dozen workers from a number of campaigns were camped on the grassy strip between a parking lot and the street. Campaign signs dotted the ground as campaigners retreated under tents for shade from the scorching sun.

Based on reporting by The Associated Press