An acrimonious divorce involving Russia’s richest woman descended into a gun battle over the country’s most successful online retailer, killing two people and wounding seven. Tatyana and Vladislav Bakalchuk,

Vladislav Bakalchuk, the estranged husband of Russia’s richest woman, was arrested and charged with murder Thursday, his lawyers said, after a deadly shootout at the Moscow office of Russia’s largest online retailer.

Here’s what you need to know about the bitter and increasingly violent struggle surrounding a company that saw $27 billion in revenues last year and what it says about doing business in Russia these days.