The Capitals announced the acquisition on the team’s Twitter page on Thursday morning.
Crocock, who is from Brantford, Ont., is listed as five-foot-11 and 178 pounds.
In 37 games with the Lumber Kings this season, Crocock had two goals, 10 assists, 12 points and 20 penalty minutes.
The Lumber Kings’ Twitter page said Crocock had requested a trade to the Capitals, who are hosting the 2013 RBC Cup Canadian junior A hockey championship from May 11 to 19.
Crocock played for Team East at the World Junior A Hockey Challenge in Yarmouth, N.S., in November.
It's expected to be a busy day as teams look to make moves before tonight's 10 o'clock roster and trading deadline.