The appearance by Pakistan Taleban leader Hakimullah Mehsud occurred one day after his group took responsibility for an attempted car bombing that fizzled in New York City's Times Square last weekend — a claim that New York officials dispute.
Late last year, the insurgent network claimed a role in the suicide attack that killed seven CIA employees at Camp Chapman in eastern Afghanistan — scene of Monday's bombing.
Afghanistan's Interior Ministry said one civilian was killed and two others were wounded in Monday's attack. A US Army spokesman said only the bomber died but two other people were wounded.
Although the New York claim remains in dispute, the series of events — including a second attack on the CIA base in four months — indicated the Pakistan Taleban are trying to show they remain a potent force despite setbacks during Pakistani military offensives in recent months.
The network has been pummeled during the last six months by relentless US missile attacks and Pakistani offensives that have pushed it from once-secure sanctuaries along the border.
In his video message, Mehsud, the Pakistan Taleban leader, said: "From now on, the main targets ... are American cities. The good news will be heard within some days or weeks."
The SITE Intelligence Group, which monitors extremists websites, said the tape appeared to have been made April 4.
Until recently, US and Pakistani officials thought Mehsud was killed by a US missile in January fired in tribal regions along the Afghan-Pakistan border. Some intelligence officials also said even if he were alive, Mehsud was no longer running the Pakistan Taleban.
In Washington last week, Pentagon spokesman Geoff Morrell said he had seen "no evidence" that Mehsud "is operational today or is executing or exerting authority over the Pakistan Taleban which he once did."
In the video, however, Mehsud, seated between two masked gunmen, boasts of being "alive and healthy."
US Army Maj. Justin Platt, spokesman for the 3rd Brigade Combat Team at nearby Salerno Camp, said the bomber blew himself up in an area where vehicles are screened before entering.
"The explosion was very strong and thick smoke covered the sky afterward," said Wali Mohammad, 17, who was working at a construction site nearby.
In December, the seven CIA employees and a Jordanian intelligence officer were killed when a suicide bomber detonated his cache of explosives inside Camp Chapman. The CIA had cultivated the bomber — a Jordanian doctor identified as Humam Khalil Abu-Mulal Al-Balawi — in hopes of obtaining information about Al-Qaeda's second in command. Al-Balawi turned out to be a double-agent.
It was one of the deadliest attacks in the history of the US intelligence agency.
The New York Police Department called the attempted car bomb in Times Square the most serious car bomb plot in the city since 1993, when Islamic extremists exploded a rented van carrying up to 1,500 pounds of fertilizer in the parking garage of the World Trade Center, killing six people and injuring more than 1,000 others.
But New York authorities have doubts that the Taleban were behind the scare, underscoring the sketchy nature of intelligence gathered from the remote, isolated Pakistani tribal regions where Taleban, Al-Qaeda and other militant groups have congregated.
Police Commissioner Raymond Kelly said police have no evidence to support the claims and noted the same group had falsely taken credit for previous attacks on US soil.
