By 1973, construction of the Naval Communications Station was completed. In the early 1970s, setbacks to United States military capabilities in the region including the fall of Saigon, victory of the Khmer Rouge in Cambodia, the closure of the Peshawar Air Station listening post in Pakistan and Kagnew Station in Eritrea, the ''Mayaguez'' incident, and the build-up of Soviet naval presence in Aden and a Soviet airbase at Berbera, Somalia, caused the United States to request, and the UK to approve, permission to build a fleet anchorage and enlarged airfield on Diego Garcia, and the Seabees doubled the number of workers constructing these facilities.