The Russian government is building an electronic intelligence-gathering facility in Nicaragua as part of Moscow's efforts to increase military and intelligence activities in the Western Hemisphere.

The signals intelligence site is part of a recent deal between Moscow and Managua involving the sale of 50 T-72 Russian tanks, said defense officials familiar with reports of the arrangement.

The tank deal and spy base has raised concerns among some officials in the Pentagon and nations in the region about a military buildup under leftist Nicaraguan leader Daniel Ortega.

Disclosure of the Russia-Nicaraguan spy base comes as three U.S. officials were expelled from Nicaragua last week. The three Department of Homeland Security officials were picked up by Nicaraguan authorities, driven to the airport, and sent to the United States without any belongings.

State Department spokesman John Kirby said the expulsion took place June 14 and was "unwarranted and inconsistent with the positive and constructive agenda that we seek with the government of Nicaragua."

"Such treatment has the potential to negatively impact U.S. and Nicaraguan bilateral relations, particularly trade," he said.

The action is an indication that President Obama's recent diplomatic overture to Cuba has not led to better U.S. ties to leftist governments in the region.

State Department officials had no immediate comment on the expulsion.

The action is an indication that President Obama's recent diplomatic overture to Cuba has not led to better U.S. ties to leftist governments in the region.

Nicaragua's Ortega has remained close to the communist Castro regime in Cuba and the leftist regime in Venezuela. He was once part of the communist Sandinista dictatorship, and after winning election as president in 2006 has shifted Nicaragua towards socialism.

No details of the intelligence site, such as its location and when it will be completed, could be learned.

However, the site could be disguised as a Russian GLONASS satellite navigation tracking station that is said to be nearing completion. GLONASS is the Russian version of the Global Positioning System network of satellites used for precision navigation and guidance.

The Nicaraguan and Russian governments in August signed an agreement to build the GLONASS station near Laguna de Najapa, north of the capital of Managua, according to Nicaraguan press reports. Other news reports said the site will be located on the Caribbean coast.

Pentagon spokesmen had no immediate comment on the Russian-Nicaraguan military and intelligence cooperation.

A State Department official said, "While any nation has the right to choose its international partners, we have been clear that now is not the time for business as usual with Russia."

Southern Command spokesman Lt. Col. David Olson said the United States respects the right of nations to modernize their defenses.

"We're aware of Russian engagements in our hemisphere," he said. "The nature of Russia's engagements in our hemisphere isn't new and similar to engagements with other nations. We are confident that our partner nations understand our desire to be their security partner of choice, as well as our commitment to work side by side with them in support of our shared interests and democratic values."

A Nicaraguan Embassy spokesman also had no immediate comment.

The tank deal involves the transfer of 50 T-72 tanks, 20 of which are reported to be en route to Nicaragua as part of a first delivery.

Protesters in Managua demonstrated in late April against the Russian tank deal. The European Press Agency reported April 28 that the protest was organized by the opposition National Coalition for Democracy and the Independent Liberal Party. One protester held a sign that read. "We do not want Russian tanks, we want bread, medicine, and peace."

Costa Rica's Foreign Minister Manuel Gonzalez also has criticized the tank sale, telling the La Prenza newspaper: "It is a matter of concern not because of a threat to Costa Rica … but because one country in the Central American region starts an arms race."

Gonzalez said the region needs more healthcare, technology, and infrastructure and not military hardware.