The killer of the Binghamton New York immigration center was identified as a Vietnamese ethics Jiverly Voong (Wong) who had been laid off by IBM. IBM announced a 5,000 job cut, and offered to relocate laid off employees to oversea positions.
It is speculated that Voong, a US citizen hated to see jobs taken away by new citizens. He walked in a citizen language preparation center, and shot 14 people dead, dozens more injured. The center helps foreigners to prepare for the citizenship test. Most of President Obama's Stimulus Package dollars have clauses to make sure the money would be going to US citizens, rather than foreigners (including those hold legal working visa). New citizens become the new competitors in the job market.
Update: the man worked for IBM until one year ago, but had been working in a local manufacture plant before he was laid off last month.
As to the name, he was quoted saying he changed his name from Voong to Wong because "Americans can't pronounce" it.
Update 2: The killer is believed to be a Chinese (Wang Linfa), from Vietnam. His father is a reputed community leader. Among died, four are Chinese citizens. One other Chinese was wounded but is expected to recover.