AS Monaco's Falcao is suspected of failing to correctly declare 5.6 million euros ($6.1 million) of income earned from image rights between 2012 and 2013 while he was at Atletico Madrid, Madrid's regional prosecutor said in a statement.

The two players are suspected of using a web of shell companies in the British Virgin Islands, Ireland, Colombia and Panama to avoid taxes on the income from their image rights.

A Spanish court last year found Barcelona's Argentine striker Lionel Messi and his father Jorge guilty of three counts of tax fraud resulting in a suspended 21-month prison sentence for both men.

It ruled Messi had defrauded the Spanish tax office of almost 4.2 million euros from 2007-09 by using a web of shell companies to avoid paying tax on income from his image rights.

Under Spanish law any sentence under two years for a non-violent crime rarely requires a defendant without a previous conviction to serve jail time.