Mullen has been hired by MSNBC in New York for an interactive-related assignment.
An MSNBC representative last week confirmed that the Wenham, Mass., agency was working for the client but would not give details. Mullen president Joe Grimaldi declined comment. Billings were not disclosed.
Quantum Leap Communications in Chicago, MSNBC's agency of record, is the only shop known to have worked for the client.
Mullen's interactive arm has grown significantly in the past few months, picking up assignments from General Motors, Oxygen Media, Dexter Shoes and the Agfa-Gevaert Group.
Rich Person, hired last year as executive vice president and director of direct and interactive services from Hill, Holliday Interactive in Boston, heads the 15-person unit.
MSNBC, a joint venture between Redmond, Wash.-based software giant Microsoft and NBC-TV in New York, provides 24-hour news service delivered via cable and the Internet.
MSNBC spent about $3 million on ads last year, according to Competitive Media Reporting. Those efforts included print, TV and Internet executions that yielded 10 million impressions on PointCast, Yahoo! and Disney's Family.com sites.
--with David Gianatasio