MEXICO CITY (AP) — There has been a huge increase in the number of businesses reporting extortion attempts by drug cartels in Mexico, according to a survey by the American Chamber in Mexico.

The survey of 541 members of the American group as well as the British and Japanese chambers of commerce in Mexico showed the percentage of firms reporting cartel extortions has doubled. Such problems were reported by 18 percent in 2012, but the number jumped to 36 percent this year even as reports of most of other types of crimes declined.