The United States is on high alert amid escalating tensions with Iran following a deadly airstrike in Syria, American officials have revealed.

The strike, which targeted a building adjacent to Iran’s embassy in Damascus, resulted in the deaths of seven members of Iran’s Revolutionary Guard. In response, the commander of Iran’s Revolutionary Guard vowed retaliation against what Tehran has deemed an attack orchestrated by Israel.

“We’re definitely at a high state of vigilance,” one US official separately told CNN, highlighting the heightened concern over potential retaliation from Iran.

US officials, speaking on condition of anonymity, have expressed fears that Iran may target Israeli military or intelligence installations in retaliation, potentially sparking further conflict in the already volatile Middle East region.

“We received a message from Iran following the strike,” one official disclosed to NBC News, emphasizing that Washington had communicated to Tehran its disavowal of any involvement in the airstrike. “We also warned Iran not to use the strike as a pretext for further escalation or attacks on US facilities or personnel,” the official added.

Another official suggested to NBC News that Iran could resort to tactics such as deploying drones or land-attack cruise missiles against Israeli diplomatic or consular facilities.

Iran has accused Israel of orchestrating the airstrike, although the Israeli military has refrained from confirming or denying its involvement.

In the aftermath of the strike, Mohammad Jamshidi, a top aide to Iranian President Ebrahim Raisi, claimed that Tehran had cautioned the US against intervening in the conflict between Israel and Iran. However, a spokesperson for the US National Security Council dismissed these claims as “simply wrong” and “Iranian spin.”

Meanwhile, the White House revealed that US President Joe Biden and Israeli Prime Minister Benjamin Netanyahu had discussed the threat posed by Iran in a recent phone call, affirming the US’s support for Israel’s defense against Iranian threats.