Four people have been indicted and could face 30 years in prison for a variation on a popular scam in which email senders claim they're trying to transfer money out of Nigeria, the US DoJ (Department of Justice) announced yesterday.

A grand jury in New York City on Wednesday returned a 10-count indictment against three of the defendants and an 11-count indictment against the fourth. Alleged victims of the four individuals lost more than $1.2m (about £690,000), the DoJ said.

Three of the defendants were arrested in Amsterdam by Dutch authorities on 21 February, based on a US criminal complaint. They are being held by the Dutch authorities pending extradition to the US. The fourth defendant, a Nigerian citizen, is a fugitive.

The four are Nnamdi Chizuba Anisiobi (also known as Yellowman, Abdul Rahman, Helmut Schkinger and Nancy White, among other aliases); Anthony Friday Ehis (also known as John J Smith, Toni N Amokwu and Mr T); Kesandu Egwuonwu (also known as KeKe, Joey Martin Maxwell and David Mark); and an unnamed defendant known as Eric Williams, Lee, Chucks and Nago.

The four are charged with one count of conspiracy, eight counts of wire fraud and one count of mail fraud. Anisiobi is also charged with one count of bank fraud.

The maximum penalty for mail and wire fraud is 20 years in prison, while the maximum sentence for bank fraud is 30 years of imprisonment. The conspiracy charge carries a maximum custodial penalty of five years.

The defendants allegedly sent spam email messages to thousands of potential victims, falsely claiming to have control of millions of dollars located in a foreign country that belonged to an individual with a terminal illness, the DoJ said.

These aren't the first charges in the email advance-fee scam, popular among Nigerian criminals. In January 2004, Dutch police arrested 52 people allegedly involved in Nigerian email and related scams, and in May 2002 South African police arrested six people on related charges. US authorities have also brought charges against other Nigerian scammers.

The defendants allegedly solicited the help of the potential victims to collect and distribute the funds to charity. In exchange for the victims' help, the defendants promised the victims a share of the large inheritance, but told victims they must pay advance fees for legal representation, taxes or bogus documentation.

After the victims wire-transferred funds to pay the 'required fees', the defendants did not deliver the funds as promised, the DoJ said.

"Global fraudsters need to know that we are determined to find and prosecute them," US Attorney Roslynn Mauskopf of the Eastern District of New York said in a statement. "Potential victims need to know that any email offering millions of dollars that requires that they send money to receive this windfall is a scheme. Delete it."