An FBI (search) informant who set himself on fire in front of the White House played a role in at least three terror investigations, court documents show.

Defense attorneys said Wednesday they are re-examining Mohamed Alanssi's (search) role in the cases against their clients, who are accused of helping fund Usama bin Laden, Al Qaeda and the Palestinian group Hamas.

"Ultimately what I'm heading for is a motion for dismissal," said Frank Hancock, the lawyer for Abad Elfgeeh, a Yemeni-born man accused of illegally sending millions of dollars overseas.

A spokesman for U.S. Attorney Roslynn Mauskopf, who filed the three cases in Brooklyn, said her office had no comment.

On Monday, Alanssi, 52, sent suicide notes to the FBI and The Washington Post complaining the government was treating him badly despite his assistance in trying to cut off the flow of money to terrorists.

Hours later, he set his clothing ablaze at the White House gate. He was in serious condition Wednesday.

Alanssi was central to the probe of Ali Hassan al-Moayad (search), a Yemeni sheik who called himself bin Laden's one-time instructor in Islamic law. Investigators recorded Alanssi and al-Moayad in Germany allegedly discussing a scheme to move money from an American Muslim to Al Qaeda (search) and Hamas, according to court filings and lawyers in the case. He's charged with conspiring to provide material support to the terror groups.

Al-Moayad's attorney, Howard Jacobs, said Alanssi's written allegations could weaken the prosecution. In one note, he said he was afraid the government might jail and torture him if he stopped cooperating. He also said FBI agents told him he would "be a millionaire" and receive permanent U.S. residency in exchange for his help.

According to court documents, Alanssi also helped the government in its case against Elfgeeh, a naturalized U.S. citizen who allegedly sent $20 million overseas illegally from his ice-cream shop in Brooklyn.

Alanssi asked Elfgeeh how to secretly move money overseas and recorded Elfgeeh, 49, advising him to give cash to another Yemeni sheik, whom prosecutors call an outspoken bin Laden supporter and advocate of Islamic jihad in Chechnya.

The probe of that sheik, Abdullah Satar, led to the conviction earlier this year of Numan Maflahi, who was sentenced to five years for lying to FBI agents about a fund-raising trip to Brooklyn by Satar in 1999.

Maflahi's lawyer said Wednesday he did not believe new information about Alanssi would affect the case, because Alanssi had not testified at trial.