Lankster is back with the Bills after being selected by Buffalo in the seventh round of the 2009 draft. He spent his rookie season in Buffalo before being cut the following year.
The 5-foot-9 player out of West Virginia spent the next four seasons with the New York Jets, where he played under new Bills head coach Rex Ryan.
Westbrooks is released less than a week after signing with the Bills.
The moves are announced Monday, when Buffalo opens a two-day session of joint practices with the Cleveland Browns at the Bills' training camp facility in suburban Rochester. The teams play a preseason game at Cleveland on Thursday.
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