Whether or not these escaped criminals had ever been servants is unknown. However, the circumstances of escape could lead to such crimes as horse theft and murder. The second man is a classic sidekick, apparently held on some minor point, possibly lack of freedom papers.
October 29, 1761
The Pennsylvania Gazette
Easton, October 14, 1761.
BROKE out of Easton Gaol, on the 14th Instant, the two following Persons, viz.
One named Thomas McCormick, who was committed on Suspicion of having murdered two Men in the Forks; he is a thick well set Fellow, about 5 Feet 8 Inches high, wears his own short black curled hair, squints with both his Eyes, somewhat marked with the Small Pox, born in Ireland, and speaks bad English, much on the Brogue, is an ill looking Fellow, much addicted to Drinking and Swearing:
Had on very little or no Cloathing, except a Piece of an old green Gown, which he wrapt about him, and a Pair of Trowsers and Shirt. 
The other of them named John Burk, a thick well set fellow, and much the same size of said McCormick, is an ill down looking Fellow, with short black Hair, and a swarthy Complexion: Had on when he went off, A brown Jacket, a blue under Jacket and Breeches, an old Felt Hat,
and are about 35 Years old each.
Whoever takes them up, and secures them in any Gaol, so as they may be brought back to Easton, shall receive for each Three Pounds Reward if taken together; but for McCormick, if taken alone, Five Pounds, paid by me JOHN JENNINGS, Sheriff.
N.B. It is supposed that they have taken a black Horse from Easton, and that they will take others the first Opportunity.
1. Based on his attire, McCormick may well have been an escaped convict laborer or sailor. The fact that he is suspected of two murders "on the Forks" indicates that he was caught while fleeing Maryland.