Local news outlets are reporting that the FBI has just confirmed that the same weapon was used to fire shots at the National Museum of the Marine Corps in Triangle on Oct. 17 and at the Pentagon on Oct. 19.

The FBI is also investigating a third shooting, which took place overnight at a Marine Corps Recruiting Station in Chantilly.

Each shooting is believed to have taken place at night, but one wonders whether the pattern of targeting Marine Corps-related sites could be worrisome to organizers of this weekend’s Marine Corps Marathon, which will take runners on a 26.2 mile course through Arlington and the District.

We’re awaiting comment from the Arlington County Police Department and the Marine Corps on whether extra security measures are being put into place.

Update on 10/27 — Citing law enforcement sources, ABC 7 reports that extra security will be in place at the marathon’s start and finish lines. Arlington police tell ABC 7 that they’re taking the recent shootings into consideration, and Pentagon police say they’ll deploy extra officers throughout the area.