The arrests of three people charged with providing material and financial support to the Pakistani Taliban came as a result of a three-year investigation, the Wall Street Journal reports.

John Gillies, special agent in charge of the FBI's Miami office, said an FBI-led regional task force began investigating suspicious transactions and wiretaps that showed a broad effort to finance the Pakistani Taliban, also known as Tehrik-e Taliban or TTP, with money raised in the U.S.

Six people, including two imams at mosques in Florida, were charged.

Hafiz Muhammad Sher Ali Khan, the 76-year-old imam of the Miami Mosque, and his son, Izhar Khan, an Imam at the Jamaat Al-Mu-mineen Mosque in Margate, Fla., were arrested in Florida. Another son, Irfan Khan, was arrested in Los Angeles.

Three others charged, Ali Rehman, Alam Zeb and Amina Khan, are on the loose in Pakistan.

The four-count indictment, announced by U.S. Attorney for the Southern District of Florida Wifredo Ferrer and the FBI, charges them with conspiring to provide support to terrorists, and with providing that support.

The indictment detailed money transfers totaling $50,000, but there was evidence that more money had been sent, Ferrer said.

Despite being an Imam, or spiritual leader, Hafiz Khan was by no means a man of peace, Ferrer said in a statement. But for law enforcement intervention, these defendants would have continued to transfer funds to Pakistan to finance the Pakistani Taliban.

And while U.S. relations with Pakistan continue to sour over the U.S. raid that killed former al Qaeda leader Osama bin Laden in Pakistan - Pakistan's parliament condemned the raid and called for a review of relations with the United States - prosecutors noted that the mosques were not charged with wrongdoing.

Prosecutors also said that the defendants were charged based on their material support to the Pakistani Taliban, not for theirs beliefs or teachings, the Journal wrote.

If convicted, each faces a maximum of 15 years in prison for each count.