WASHINGTON — On Wednesday evening, a pair of US Air Force B-2 Spirit bombers carried out air strikes against the Islamic State in Libya, US defense officials said on Thursday.

The Spirit of Pennsylvania and Spirit of Georgia, bombers attached to the 509th Bomb Wing at Whiteman Air Force Base in Missouri, dropped more than 100 precision-guided munitions on two Islamic State camps approximately 28 miles southwest of Sirte.

When asked why the B-2, the world's most technologically-advanced strategic bomber was selected for this particular mission, which killed approximately 80 Islamic State fighters, US Air Force spokesman Col. Patrick Ryder said it gave "military commanders options."

"Because of it's range, because of it's payload capacity, it gives military commanders options. So in this particular case, carrying a GBU-38, a 500 pound JDAM, the B-2 can carry up to 80 of those," Ryder told reporters.

Additionally, the B-2, with a payload capacity of 40,000 pounds, is able to loiter for long periods of time, which gives it "persistence and flexibility if and when additional strikes are warranted," US Air Force spokesman Capt. Mark Graff said in a statement.

A B-2 Spirit flies over the Power in the Pines Open House and Air Show on Joint Base McGuire-Dix-Lakehurst on May 14, 2016. Tech. Sgt. Matt Hecht/US Air Force

The price tag of Wednesday's mission was colossal.

The pair of B-2s flew for 34 hours at an operating cost of approximately $130,000 per flight hour. That comes out to roughly $4.4 million a piece or $8.8 million for the duo. Additionally, there were roughly 15 aerial refueling aircraft involved in the mission, not to mention the cost of 100 JDAMs.

The B-2's last combat deployment was in March 2011 when three aircraft were used in Operation Odyssey Dawn over Libya. Currently, there are 20 B-2's in the US Air Force's inventory.