China is expanding security partnerships with island states across the Pacific, according to American lawmakers and officials wary of the communist regime moving to curtail U.S. influence in a critical region.

“Through foreign assistance, elite capture, and robust public messaging campaigns, the PRC has moved aggressively to assert itself in the Pacific Islands,” Assistant Secretary Daniel Kritenbrink, the lead State Department official for East Asia and the Pacific, told the Senate Foreign Relations Committee on Thursday.