Osama Bin Laden’s successor threatens America

US: Al Qaeda leader, Ayman al-Zawahri in an online video message issued a warning to the United States of the "gravest consequences" if Boston marathon bomber Dzhokhar Tsarnaev or any other Muslim prisoner is executed in the US.Tsarnaev carried out the Boston bombings alongside his older brother Tamerlan, who was killed in a gun battle with police.
Tsarnaev, was sentenced to death in 2015 by lethal injection for the 2013 bomb attack, which left three people dead and more than 260 wounded.

“If the U.S. administration kills our brother the hero Dzhokhar Tsarnaev or any Muslim, it ... will bring America’s nationals the gravest consequences,” Zawahri said.

Zawahri urged Muslims to take captive as many Westerners as possible, especially those whose countries had joined the "Crusaders' Campaign led by the United States."
He said that the Western captives could then be exchanged for Muslim prisoners adding that western powers "are criminals and they only understand the language of force".

The video, did not give any indication of Zawahri's location, whose base is believed to be close to the Afghan-Pakistan border.
Zawahri, took over al Qaeda's leadership after U.S. forces killed Osama bin Laden in 2011.
Tsarnaev is being held at the "Supermax" high-security prison in Florence, Colorado.