Dozens of West Point cadets have cheated in one of the biggest exam scandals to hit the elite US military academy in decades, officials say.

More than 70 students were accused of breaking West Point's Cadet Honor Code in a math test while studying remotely because of the coronavirus pandemic.

Most of the cadets have admitted cheating on May's exam.

Instructors became suspicious when they noticed irregularities while marking the calculus tests.

Seventy-two of the cadets involved are in their first year, while another is a second-year student.

Fifty-five who have admitted cheating have been sent on a six-month rehabilitation programme and will be on probation for the rest of their time at West Point, report US media.

Some cases were dropped for lack of evidence or because the cadets dropped out, while several others face hearings before a board composed of fellow students to determine if they will be penalised or expelled.

The Cadet Honor Code, engraved in stone on a memorial at West Point, reads: "A cadet will not lie, cheat, steal, or tolerate those who do."

"The honour system at West Point is strong and working as designed," Lt Gen Darryl Williams, the academy's superintendent, said in a statement to USA Today.

"We made a deliberate decision to uphold our academic standards during the pandemic. We are holding cadets to those standards."

The Associated Press news agency reports that it is the biggest cheating scandal to hit West Point since 1976 when 153 cadets were expelled or resigned for cheating on an electrical engineering exam.

Amid complaints about how that investigation was handled, most of the disgraced students were readmitted and allowed to graduate.

West Point, which is about 60 miles (100km) north of New York City, has turned out some of America's best-known generals, including Civil War rivals Ulysses S Grant and Robert E Lee, and World War Two commanders Douglas MacArthur and Dwight Eisenhower./BBC