The United States is “gratified ” that Pakistan has arrested three suspects for their alleged role in the failed car bomb attempt in Times Square of New York City, the U.S. State Department said on Wednesday.

“We believe strongly that Faisal Shahzad had help within Pakistan,” State Department spokesman Philip Crowley said, referring to the lead suspect in the May 1 attempted car bombing. An American citizen born in Pakistan, Shahzad has pleaded guilty to terrorism and weapons charges in the United States in connection with the bomb attempt.

“We have worked very extensively and closely with Pakistani authorities,” Crowley said at a press briefing. “There is an ongoing criminal investigation, but we are gratified that Pakistan has made some arrests in this case.”

The three accused accomplices of Shahzad are all Pakistani nationals. The Pakistani authorities on Wednesday formally acknowledged their arrest, saying terrorism charges will soon be brought against them.

“Obviously, the fate of those particular defendants is in the hands of the Pakistani judicial system,” Crowley said.