The Spanish government is currently looking into several of the country's top poker pros over a back taxes issue. While Spain has always required that grinders pay taxes on their winnings, the matter has suddenly become much more pressing lately.

In order to catch players who owe back taxes, government officials are reportedly looking at the HendonMob.com site, which shows live tournament statistics on nearly every player in history; the goal is to see if there are discrepancies between what's been reported and what HendonMob shows. Here's a quick look at some of the players who are at the top of Spain's all-time winnings list:

1. Carlos Mortensen - $10,811,436
2. Raul Paez Corral - $1,666,245
3. Juan Maceiras Lapido Jr. - $1,082,049
4. Dragan Kostic - $922,347
5. Raul Mestre - $916,089

Now we're not saying that these players in particular warrant further investigation over the tax issue. However, it's grinders like these that the Spanish government is paying special attention to as they try to match declared winnings to HendonMob's statistics.

This ordeal is somewhat similar to what Sweden's government recently did to many poker players throughout their nation. In an effort to discover which players owe back taxes, Swedish police raided certain pros' homes and confiscated laptops and other potential evidence. Following this invasion of privacy, many Swedish grinders complained about how they were treated by the government.

Luckily Spain doesn't appear to be going this far yet. However, they could be headed down the same path if they decide to go after online poker players as well. Since regulating the game over the summer, Spain has seen a large spike in online poker players. And it's likely that they'll want to squeeze as many tax dollars as they can from profitable pros.