A pair of senior Yahoo executives is leaving the beleaguered Internet company, continuing a steady exodus of executives that began more than two years ago.

Usama Fayyad.

The latest to leave are Jeff Weiner, executive vice president of the network division, and Usama Fayyad, chief data officer and executive vice president of research and strategic data solutions, according to a person with knowledge of the situation.

A Yahoo spokesman said the company doesn’t comment on rumors and speculation.

Mr. Weiner, who was recruited to Yahoo by former Chief Executive Terry Semel in 2002, was in charge of the Yahoo portal and its myriad services, including search, mail, My Yahoo, Groups, Flickr, Answers and media properties like news, finance, sports and entertainment. Essentially Mr. Weiner oversaw everything that consumers touched except for mobile services.

A hard-driving executive, Mr. Weiner had a mixed tenure. Well-respected by many inside Yahoo, Mr. Weiner helped maintain Yahoo dominance in a number of areas, including mail and news. But he also presided over the steady erosion of the company’s search business, which contributed to Yahoo’s downfall. Microsoft and others were also unable to compete against Google in search.

Mr. Weiner is expected to come back from a four-week paternity leave on Monday and leave Yahoo shortly thereafter. He has accepted a dual appointment at two venture capital firms, Accel Partners and Greylock Ventures, as an entrepreneur in residence, the person with knowledge of the situation said.

Meanwhile, Dr. Fayyad told his staff yesterday that he would be leaving and his departure is expected to be officially announced later today. Dr. Fayyad was the data guru at Yahoo, the person in charge of mining the terabytes of data collected by the company to improve things like the targeting of ads and content to Yahoo users. He was also in charge of Yahoo’s well-respected research organization.

In addition to Mr. Weiner and Dr. Fayyad, Yahoo veteran Jeremy Zawodny announced on his blog that he is also leaving. Mr. Zawodny joined Yahoo in 1999 and helped start Yahoo’s developer network and was a prominent backer of open source software inside the company. Mr. Zawodny said that he is leaving because of a new opportunity, not because of the Yahoo’s uncertain future.

Reports of Mr. Weiner’s and Dr. Fayyad’s departures have been swirling on other blogs, including AllThingsD and Valleywag.