The United States is planning a weeks-long bombing campaign in the Middle East in response to a drone attack in northeastern Jordan that killed three American soldiers, US officials told NBC News on Thursday.

The officials said that President Joe Biden has decided to target several targets, and that the targets are expected to include Iranian targets outside Iran, and the campaign will include strikes and electronic operations.

Other reports stated that the United States is considering targeting Iranians in Iraq and Syria or the Iranian Navy.

President Biden and Defense Secretary Lloyd Austin will receive the bodies of the three soldiers at Dover Base, Delaware (President Biden's state) on Friday, and the start of the process will likely coincide with the reception and burial ceremony of the bodies.

While the potential targets are not inside Iran, direct attacks on the Iranian military could lead to all-out war between the United States and Iran. The United States is considering taking this course of action despite the Pentagon's admission that it has no evidence of direct Iranian involvement in the drone attack in Jordan.

The Pentagon said the Jordanian attack had "effects" on Kataib Hezbollah, one of the main Shiite militias in Iraq. The United States says Iran is only responsible because it arms Kataib Hezbollah and other Shiite militias. US officials told the New York Times that while Iran is arming and funding Shiite militias, there is no evidence that Tehran is “making the decision.”

John Kirby, spokesman for the White House National Security Council, said on Wednesday that US intelligence indicates that the drone attack was carried out by the Islamic Resistance in Iraq, a shadowy umbrella group for Iraqi Shiite militias.

The Islamic Resistance (in Iraq) has claimed responsibility for many of the 160 attacks launched against American forces in Iraq and Syria since mid-October. The attacks began in response to US support for the Israeli massacre in Gaza.

Kirby also hinted at the possibility of a long-term bombing campaign. "The first thing you see won't be the last," he said, adding that it won't be a "one-off."

Iran pledged to respond to any American attacks on Iranians in the region. Amir Saeed Iravani, Iran's ambassador to the United Nations, said, "The Islamic Republic will respond firmly to any attack on the country, its interests, and its citizens under any pretext."