If he is dead, it would mark a major coup for the Americans hard on the heels of the killing of Osama bin Laden in a May 2 U.S. Navy SEALs strike on his hideout near Islamabad, Pakistan's capital.
The Long War Journal, which monitors international terrorism, reported a purported photo of Kashmiri's body posted on a jihadist Web site by a Pakistani group associated with Kashmiri was actually that of Abu Dera Ismail Khan, a fighter of the Lashkar-e Toiba, or Army of the Pure, killed in the November 2008 terrorist attack on Mumbai.
Kashmiri, who is also a leader of the Harakat ul Jihad al-Islami and an elite jihadist unit known as Brigade 313, was reported killed with other fighters in a missile attack Friday night by a U.S. unmanned aerial vehicle in the Wana area of South Waziristan, an Islamist stronghold in northern Pakistan.
HUJI spokesman Abu Hanzla Kashir reported Kashmiri's death in a written statement, monitored by the SITE Intelligence Group, less than 24 hours after the attack and vowed to attack the United States to avenge the slaying.
The statement was posted on the Shamukh al-Islam forum, a Web site frequented by jihadists linked to al-Qaida, along with the purported image of Kashmiri's corpse.
There were also misspellings in the text of the statement, including the HUJI's name, which cast further doubt on its veracity.
Several Taliban leaders in Pakistan, along with Pakistani security officials, have said that Kashmiri was killed in Friday's missile strike.
But U.S. intelligence officers contacted by The Long War Journal Sunday said they couldn't confirm that Kashmiri was dead because they couldn't enter Waziristan to examine the body or check its DNA.
One said the jihadists may have reported Kashmiri's death as part of a deception plan, possibly to throw U.S. forces off his trail but there is no record that Islamist groups have sought to fake the death of a prominent figures in the past.
Still, the reported killing of Kashmiri came within a few days of reports that joint teams of U.S. CIA and Pakistani Inter-Services Intelligence directorate agents had been formed to hunt down top Taliban and al-Qaida leaders, including Kashmiri.
The establishment of these units indicates a new sense of cooperation between the Americans and Pakistanis, who have long been distrustful of each other.
The Americans say many officers and factions within the ISI, Pakistan paramount intelligence organization, sympathize and work with the Taliban, al-Qaida and the various Islamist groups operating in Pakistan and Afghanistan.
There are other aspects of the reported killing of Kashmiri that merit attention.
The nighttime drone attack on Wana was mounted five days after the disappearance of prominent Pakistani journalist Syed Saleem Shahzad of the Asia Times Online who specialized in terrorism and security affairs and had contacts with Kashmiri.
Shahzad vanished in Islamabad May 29 after he'd been questioned at ISI headquarters about a report he published that al-Qaida attacked a naval base in Karachi May 22 in retaliation for the arrest of two naval officers suspected of links with the group.
That attack, purportedly masterminded by Kashmiri, was a major embarrassment for the Pakistani military in the wake of the Americans' killing of bin Laden, who had been living in plain sight in a garrison town for several years, possibly with the knowledge of Pakistani authorities.
Shahzad had interviewed Kashmiri in September 2009, after the jihadist chieftain had been reported killed in a UAV attack.
The 40-year-old journalist had told colleagues he feared the ISI was out to kill him because of his contacts with Kashmiri and other jihadists.
Shahzad's body, showing signs of torture, was found May 31 on a canal bank 80 miles southeast of Islamabad. The ISI denied any involvement in his death.
Meantime, two senior operatives with ties to al-Qaida, a commander associated with bin Laden and a leader of the Islamic Movement of Uzbekistan, were captured last week in Afghanistan.