(CNN) Former House Speaker Dennis Hastert sexually abused at least four boys when he coached wrestling at a high school in Illinois decades ago, federal prosecutors said.

In documents released Friday, prosecutors detailed stunning allegations against Hastert, the longest-running Republican speaker of the House.

Hastert walks through Statuary Hall on his way to the House floor to make his farewell address to Congress on November 15, 2007. He formally resigned on November 26, 2007, after 20 years in office.

Hastert walks through Statuary Hall on his way to the House floor to make his farewell address to Congress on November 15, 2007. He formally resigned on November 26, 2007, after 20 years in office.

Hastert announces that he will not seek re-election for a 12th term on August 17, 2007, as he stands on the steps of the old Kendall County courthouse in Yorkville, Illinois.

Hastert announces that he will not seek re-election for a 12th term on August 17, 2007, as he stands on the steps of the old Kendall County courthouse in Yorkville, Illinois.

Hastert celebrates his re-election to an 11th term in Congress on November 7, 2006, with his wife, Jean, at a victory party in the Baker Hotel in St. Charles, Illinois. Republicans lost their majority in the House, meaning Hastert lost his position as speaker when the new Congress started on January 4, 2007.

Hastert celebrates his re-election to an 11th term in Congress on November 7, 2006, with his wife, Jean, at a victory party in the Baker Hotel in St. Charles, Illinois. Republicans lost their majority in the House, meaning Hastert lost his position as speaker when the new Congress started on January 4, 2007.

Vice President Dick Cheney greets Hastert before Latvian President Vaira Vike-Freiberga speaks to a joint meeting of Congress in June 2006. Earlier that month, Hastert had surpassed Joe Cannon to become the longest-serving Republican speaker of the House.

Vice President Dick Cheney greets Hastert before Latvian President Vaira Vike-Freiberga speaks to a joint meeting of Congress in June 2006. Earlier that month, Hastert had surpassed Joe Cannon to become the longest-serving Republican speaker of the House.

House Rules Chairman David Dreier and Hastert hold a news conference on a GOP lobbying reform package, which included banning privately funded travel and eliminating access to the House floor for former members who are registered lobbyists. On January 3, 2006, Hastert donated $70,000 of campaign contributions from companies associated with lobbyist Jack Abramoff to charity after Abramoff pleaded guilty to corruption charges.

House Rules Chairman David Dreier and Hastert hold a news conference on a GOP lobbying reform package, which included banning privately funded travel and eliminating access to the House floor for former members who are registered lobbyists. On January 3, 2006, Hastert donated $70,000 of campaign contributions from companies associated with lobbyist Jack Abramoff to charity after Abramoff pleaded guilty to corruption charges.

Hastert stands behind President George W. Bush as he signs Medicare legislation in December 2003. Hastert fought hard for the bill in the House, leading to a three-hour vote on November 22, 2003.

Hastert stands behind President George W. Bush as he signs Medicare legislation in December 2003. Hastert fought hard for the bill in the House, leading to a three-hour vote on November 22, 2003.

Hastert is sworn in as speaker of the House of Representatives on January 6, 1999, during the opening session of the House in Washington. Hastert replaced Newt Gingrich.

Hastert is sworn in as speaker of the House of Representatives on January 6, 1999, during the opening session of the House in Washington. Hastert replaced Newt Gingrich.

Dennis Hastert in 1985 as a member of the Illinois House of Representatives, where he served from 1980 to 1986.

Dennis Hastert in 1985 as a member of the Illinois House of Representatives, where he served from 1980 to 1986.

The revelation comes days before his April 27 sentencing in a financial violation case . He pleaded guilty last year to structuring money transactions to evade reporting where he took massive amounts of funds he was withdrawing.

Investigators said the transactions involved $3.5 million he paid in hush money to one of his accusers.

Prosecutors listed four boys Hastert allegedly abused at a high school in Yorkville, Illinois.

An additional one -- a fifth student -- died years later, according to the document.

Accuser allegedly paid off

The accusations came to light after investigators found out he was paying an ex-student to stay quiet about sexual abuse allegations, prosecutors allege.

The student was among four others who told investigators he abused them, including one who was 14 at the time, the documents allege.

The allegations date to the 1960s and 1970s, according to the prosecutors' court filing.

Hastert will not face sexual abuse charges because the statutes of limitation have expired.

Massages, sex acts alleged

All those who accused him of sexual abuse were wrestlers at the high school, according to the documents.

In two separate cases, Hastert massaged one boy each in a locker room and performed unspecified sexual acts on them, prosecutors allege.

In another instance, he allegedly massaged a boy's groin area and singled him out to stay in his hotel room during a wrestling camp.

Another accuser said Hastert touched him inappropriately in a "very weird" way while he was a student, prosecutors said.

"The actions at the core of this case took place not on the defendant's national public stage but in his private one-on-one encounters in an empty locker room and a motel room with minors that violated the special trust between those young boys and their coach," prosecutors said.

During his time at Yorkville High School, Hastert was a beloved coach. He was named Illinois coach of the year after leading the wrestling team to the state championship.

Apology

In a statement Saturday, Hastert 's attorney Thomas Green said the former speaker "acknowledges that as a young man he committed transgressions for which he is profoundly sorry."

"He earnestly apologizes to his former students, family, friends, previous constituents and all others affected by the harm his actions have caused," Green said.

Hastert has already suffered "profound humiliation and public shaming" and is in poor health, Green added.

Hastert was hospitalized with various ailments late last year , including a stroke and sepsis. His attorneys have asked for probation instead of jail time in the financial case.

"He accepts responsibility for his conduct, seeks no special consideration, and is prepared to receive the court's sentence," Green said.

Before details of the sexual abuse allegations came to light, Hastert also apologized this week for an unspecified misconduct.

Hastert served as the Republican speaker of the House between 1999-2007.