In response to hostile behavior and apparent acts of aggression by Iran, the US military has been sending additional firepower to the Middle East since May.

The US has sent a carrier strike group, bombers, fighters, amphibious assault vessels, missile defense batteries, and ground troops to deter Iran.

The Department of Defense announced Friday that it has increased the number of US forces in the Middle East by 14,000 since May.

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When tensions with Iran spiked in May, the US began sending significant firepower to the Middle East to confront possible threats. Since that time, the US has increased the number of US forces in the region by 14,000, the Department of Defense announced Friday.

The US sent the USS Abraham Lincoln carrier strike group and a bomber task force to the US Central Command area of responsibility in May. Those assets were quickly followed by additional deployments of fighters, amphibious assault vessels, and air-and-missile defense batteries.

As the situation with Iran worsened with a string of troubling tanker attacks and other acts of aggression said to have been carried out by Iranian forces, the US sent around two thousand additional ground troops into the area to improve US warfighting capabilities. The US also sent additional fighter and reconnaissance aircraft.

Some assets may have left the region as others arrived.

Following a relative lull in tensions, two Saudi oil sites came under fire, and the US has pinned the blame on Iran. The US made the decision in September to send one Patriot battery, four Sentinel radar systems, and approximately 200 support personnel to Saudi Arabia.

On Friday, the Department of Defense announced that it was sending two fighter squadrons, one air expeditionary wing, two Patriot batteries, and one Terminal High Altitude Area Defense (THAAD) battery to the region. In the last month, the US has moved an additional 3,000 troops into the area.

"As we have stated, the United States does not seek conflict with the Iranian regime, but we will retain a robust military capability in the region that is ready to respond to any crisis and will defend U.S. forces and interest in the region," the Pentagon said in a statement.