After several lawmakers were hassled in airports, federal authorities on Saturday increased security for members of Congress when they travel to and from Washington through the inauguration, according to an internal memo obtained by Axios.

Why it matters: The unusual new safety measures reflect the increased incidents of angry Americans confronting lawmakers, and the hostile aftermath of Wednesday’s siege of the U.S. Capitol.

A “House Alert” sent to members on Saturday said that the House Sergeant at Arms “and the U.S. Capitol Police have partnered with the Washington Metropolitan Airports Authority and the United States Air Marshals to increase security for Members of Congress while traveling to and from Washington D.C.”

• The “Travel Security Notification for Members of Congress” encouraged lawmakers to submit their flight itineraries to House security officials, who “will make notifications to the appropriate law enforcement agencies to ensure an increased security posture.”
• “Agents from the U.S. Capitol Police will also be stationed at BWI, IAD and DCA airports through the Inauguration to assist in security coordination.”

Members and staff were encouraged to “remain vigilant of their surroundings and immediately report anything unusual or suspicious.”

Video was posted Tuesday showing Sen. Mitt Romney (R-Utah) being heckled in the Salt Lake City airport. On Friday, Sen. Lindsey Graham (R-S.C) was called a “traitor” and “verbally harassed” by at least a couple dozen Trump supporters at Washington Reagan National Airport, Politico reported from video.

• Over the New Year’s holiday weekend, vandals defaced the homes of both House Speaker Nancy Pelosi and Senate Majority Leader Mitch McConnell.

Zoom out: The Federal Aviation Administration also said Saturday that the agency will “pursue strong enforcement action against anyone who endangers the safety of a flight,” after unruly behavior took place on several flights to and from the Washington, D.C. area this week.