WASHINGTON--US websites that allow employers to transfer money to far-flung employees may have been used to secretly finance the assassination of a Hamas leader in Dubai, a US newspaper reported Saturday.

The Wall Street Journal reported Saturday that US investigators cooperating with Dubai police believe several US-based companies were used to cover the tracks of whoever funded the January operation.

The murder of Mahmud al-Mabhuh, a founder of the military wing of Hamas, was carried out by a team of undercover assassins that Dubai alleges were dispatched by Israeli intelligence agency Mossad.

Israel has said there is no evidence linking it to the assassination, but the Journal pointed out that the case is "delicate" for the United States, which is a key Israeli ally but also has good relations with Dubai and the United Arab Emirates as a whole.

The newspaper, citing unnamed US and international investigators, said there was no indication that companies used to transfer money to the assassins knew of their role in the plot.

"Instead, US investigators believe, suspects might have posed as freelancers in order to get money in a way that obscured their funding source, and used the money for operational expenses, such as buying plane tickets," the Journal said.

The money was loaded onto pre-paid credit cards by online payment companies that are often used by firms that need to pay workers in remote locations where it can be difficult to cash checks or wire payments, the newspaper said.

The report said it was unclear how US investigators had managed to trace the suspected money transfers.

Dubai earlier this year identified 13 US-issued pre-paid card accounts, but all those linked to the cards had used false passports.

Mabhuh was found dead in his room in the Al Bustan Rotana hotel near Dubai airport on January 20. He had been drugged and then suffocated.

Dubai police released extensive surveillance camera footage afterwards that they said showed a team of 27 suspected assassins linked to Mossad.