SAN BERNARDINO, Calif. — While it is unclear how Tasheen and Syed Farook-the couple that shot and killed 14 people here Wednesday-were radicalized, judging from pictures of their weapons and ammunition released Thursday evening by officials, it appears they were, at least partially, militarized.

The two AR-15s – a California compliant DPMS and a Smith and Wesson M&P 15 – both had optics, grips and slings mounted in similar places, indicating a certain degree of interoperability between the two weapons.

The slings are commonly used in the military because of how easy they are to fit around body armor and attach to the rifle.

Additionally, the grips at the front of the rifle – known as Grip Pods – are standard issue in some branches of the military. The front grip can double as a place to hold the rifle and, with a push of a button, deploy a small bipod for additional stability.

The two optics appeared to be red dot sights-potentially Aimpoint M2s (a frequently-used optic in the U.S. Army). The one on the DPMS seems to have been blown in half-potentially from the gun battle between the two shooters and law enforcement.

Additionally, the ammo recovered at the scene was 5.56mm attached to stripper clips, indicating the ammo was bought in bulk and potentially from leftover military stocks. The military issues ammo in 10 round stripper clips so the bullets can be reloaded into magazines quicker with the use of a small adapter.

While officials have said the shooters were not wearing body armor, pictures from the scene indicate they were wearing tactical belts with pouches meant to hold magazines. Police officers and soldiers frequently wear magazines and additional gear on their body armor-namely around their chest.

The shooters’ setup and gear used indicate a certain degree of know-how when it comes to outfitting. While their equipment doesn’t indicate tactical proficiency, it does however show a level of research and preparation not commonly seen in domestic mass-shootings.