Drug Enforcement Administration chief Robert C. Bonner has told agency employees that DEA's director of operations, Stephen H. Greene, will become acting deputy administrator starting today.

Spokesman Frank Shults said Bonner did not indicate whether Greene was his choice to become the permanent deputy administrator, the number two job in the agency and a position that requires nomination by the president and confirmation by the Senate.

Greene will replace Terrence M. Burke, once considered a candidate to head the agency after John C. Lawn retired as administrator last March. Bon- ner did not announce Burke's new position.

Greene joined the federal government as a special agent in Baltimore.

A decorated Marine, Greene headed the Saigon field office when the South Vietnamese government fell in 1975. He also served in Hong Kong, Bangkok, Los Angeles and Washington.

Burke has been acting deputy administrator since 1989, but was never nominated for the post. Burke also served as acting administrator between Lawn's retirement and Bonner's swearing in last August.

As acting chief, Burke shook up the DEA's top ranks last May. Among other changes, he shifted David L. Westrate -- highly visible because of his frequent testimony before Congress -- from assistant administrator in charge of operations to assistant administrator for planning and inspection. At the same time, Burke moved Greene, Westrate's old deputy, into Westrate's operations job.