Massachusetts State Police revealed more than they intended in a tweet about the gas leak explosions last week. In a screengrab of a map of emergency responses to fires and explosions, several left-wing and Black rights groups’ pages can be seen bookmarked in the browser.

MSP deleted the original tweet and replaced it with a cropped version (at the time of writing the Facebook post still had the bookmarks bar clearly visible). Among the bookmarked pages are the Facebook group page for Mass. Action Against Police Brutality (MAAPB), the Coalition to Organize and Mobilize Boston Against Trump (COMBAT), a site called the "Resistance Calendar," which provides information about anti-Trump rallies and events, and a Facebook group that hasn’t been identified but is labeled as “MA Activist.”

In an emailed statement, David Procopio, the director of media communications for MSP, said the police only keep tabs on groups so they can plan for any large gatherings.

“We do not collect information about—nor, frankly, do we care about—any group’s beliefs or opinions,” Procopio wrote. “We, obviously, need to know if large numbers of people, for whatever reason, are going to be on public roadways or public spaces, so that we may ensure the safety and rights of those who have gathered as well as of the members of the public around them.”

There is a notable lack of any right-wing groups saved in the tab, and because many of the Facebook groups are largely inactive (COMBAT stated that it had not met in over a year), critics are skeptical of the official response.

“COMBAT has actively resisted demonstrations held by members of the so-called “‘alt-right”’, who have appeared in public bearing weapons and clad in racist symbols and flags,” COMBAT posted in a statement on its Facebook page. “ We question why time is being spent monitoring a group such as COMBAT, who actively condemns these violent ideologies, rather than on these groups who appear in public with weapons.”

Kade Crockford, director of the Technology for Liberty Program at the American Civil Liberties Union (ACLU) of Massachusetts, told the Guardian they were “appalled, but not surprised” by the revelation.

“They should disclose the groups they’re monitoring,” Crockford said. “I encourage the state police to release a list of all organizations’ Facebook pages they monitor for policing large events.”