Police are investigating after a ball boy for the Oklahoma City Thunder tweeted death threats to Houston Rockets guard Patrick Beverley. Thunder All-Star Russell Westbrook was hurt when Beverley tried for a steal in the second quarter of Game 2 last Wednesday and ran into his knee. Westbrook had knee surgery Saturday and is out for the season. The tweets were deleted as of Saturday night, but the Houston Chronicle reported a tweet from the handle @MitchellBrwn said: 'Patrick Beverly (sic), I'm coming to kill you.' He later sent another one with Beverley's Twitter name, saying: '(@pavbev21 I'm coming to kill you.' He later apologized in one tweet and then said he was hacked in another post. The account has since been taken down. Oklahoma City police Captain Dexter Nelson tells The Associated Press that their department is working with the Houston police and the NBA to investigate the threats. The Thunder says in a statement that they 'do not condone h