Police broke up an escalating argument at a polling station on election day at the Rockport Public Library.

The Midcoast Villager reports that a man collecting signatures to keep transgender athletes out of girls’ sports got into an argument with a girl carrying a sign opposing his effort.

The election warden then called police, who arrived and reported that the man moved along before the argument developed any further.

Transgender athletes in girls’ sports have become a hot-button issue since President Trump and Governor Janet Mills tangled over Maine’s policy allowing the practice earlier this year.

The Villager reports the man was collecting signatures for Protect Girls’ Sports in Maine, which is trying to get a measure on next year’s ballot seeking to divide sports into three groups — biological girls/women, biological boys/men and those who identify as part of other groups.

Former Republican Governor Paul LePage posted a video on his Facebook page Monday urging voters to sign the petition at the polls Tuesday,

LePage is running against incumbent Democratic Congressman Jared Golden in next year’s election.