Pentagon has already deployed 750 paratroopers in response to Tuesday’s attack on the American embassy in Iraq. But the U.S. military is not taking chances and is reportedly readying 4,000 more soldiers just in case the situation escalates.

The U.S. embassy in Baghdad was attacked on Tuesday by around 6,000 pro-Iran Shiite militia fighters who chanted “Death to America!” while setting walls on fire, Daily Mail reported. Fortunately, there were no American casualties as 100 Marines quickly responded and dealt with the mob.

“The U.S. Embassy in Iraq is, & has been for hours, SAFE! Many of our great Warfighters, together with the most lethal military equipment in the world, was immediately rushed to the site,” President Donald Trump tweeted an update on the situation. “Thank you to the President & Prime Minister of Iraq for their rapid response upon request.”

At the moment, 750 paratroopers have been deployed in response to the attack. “This deployment is an appropriate and precautionary action taken in response to increased threat levels against U.S. personnel and facilities, such as we witnessed in Baghdad today,” Secretary of Defense Mark Esper said on Tuesday.

Meanwhile, around 4,000 paratroopers from the Division Ready Brigade (DRB) have been alerted for possible deployment as well, according to Fox News. The outlet said that the soldiers within the 96-hour alert window which started on Tuesday.

Secretary of State Mike Pompeo labeled the embassy attack as state-sponsored terrorism. Blaming Iran for the incident, Pompeo issued a statement saying that the attack was “abetted by Iranian proxies.”

President Donald Trump also condemned the embassy attack. In a post on social media, he vowed that Iran will be held accountable for the incident.

“Iran will be held fully responsible for lives lost, or damage incurred, at any of our facilities,” Trump tweeted. “They will pay a very BIG PRICE! This is not a Warning, it is a Threat. Happy New Year!”

Analysts believe that the embassy attack was in retaliation for the recent U.S. airstrikes. The U.S. military bomb carried out Kataeb Hezbollah bases which killed around two dozens of its fighters.