S.W.O.R.D.

 S.W.O.R.D. is an agency offshoot of S.H.I.E.L.D., chartered to observe and deal with alien incursions, making peaceful first contact, if possible. They are also the agency with jurisdiction to apprehend illegal extraterrestrials.  They are based on the Damocles, the captured flagship of Kang the Conquerer, and headed by Abigail Brand.  Their government liaison is Henry Gyrich.

There is at least one alien in their employ, taken from the Kree during their attempted incursion.