U.S. Secretary of State Marco Rubio on Saturday threatened bounties on the heads of Afghanistan?s Taliban leaders, sharply escalating the tone as he said more Americans may be detained in the country than previously thought.

The threat comes days after the Afghan Taliban government and the United States swapped prisoners in one of the final acts of former U.S. President Joe Biden.

The new top U.S. diplomat issued the harsh warning via social media, in a rhetorical style strikingly similar to his boss, President Donald Trump.

?Just hearing the Taliban is holding more American hostages than has been reported,? Rubio wrote on X.

?If this is true, we will have to immediately place a VERY BIG bounty on their top leaders, maybe even bigger than the one we had on bin Laden," he said, referring to the al-Qaida leader killed by U.S. forces in 2011.

Rubio did not describe who the other Americans may be, but there have long been accounts of missing Americans whose cases were not formally taken up by the U.S. government as wrongful detentions.

In the deal with the Biden administration, the Taliban freed the best-known American detained in Afghanistan, Ryan Corbett, who had been living with his family in the country and was seized in August 2022.

Also freed was William McKenty, an American about whom little information has been released.

The United States in turn freed Khan Mohammed, who was serving a life sentence in a California prison.

Mohammed was convicted of trafficking heroin and opium into the United States and was accused of seeking rockets to kill U.S. troops in Afghanistan.

The United States offered a bounty of $25 million for information leading to the capture or killing of Osama bin Laden shortly after the September 11, 2001, terror attacks, with Congress later authorizing the secretary of state to offer up to $50 million.

No one Is believed to have collected the bounty for bin Laden, who was killed in a U.S. raid in Pakistan.

Harder line on Taliban?

Trump is known for brandishing threats in his speeches and on social media. But he is also a critic of U.S. military interventions overseas and in his second inaugural address Monday said he aspired to be a ?peacemaker.?

In his first term, the Trump administration broke a then-taboo and negotiated directly with the Taliban ? with Trump even proposing a summit with the then-insurgents at the Camp David presidential retreat ? as he brokered a deal to pull U.S. troops and end America?s longest war.

Biden carried out the agreement, with the Western-backed government swiftly collapsing and the Taliban retaking power in August 2021 just after U.S. troops left.

The scenes of chaos in Kabul brought strong criticism of Biden, especially when 13 American troops and scores of Afghans died in a suicide bombing at the city?s airport.

The Biden administration had low-level contacts with Taliban government representatives but made little headway.

Some members of Trump?s Republican Party criticized even the limited U.S. engagements with the Taliban government and especially the humanitarian assistance authorized by the Biden administration, which insisted the money was for urgent needs in the impoverished country and never routed through the Taliban.

Rubio on Friday froze nearly all U.S. aid around the world.

No country has officially recognized the Taliban government, which has imposed severe restrictions on women and girls under its ultra-conservative interpretation of Islam.

The International Criminal Court?s chief prosecutor on Thursday said he was seeking arrest warrants for senior Taliban leaders over the persecution of women. (AFP: Text, Excluding Headline)

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