It was Lithuania's first joint project with US CYBERCOM in response to cyber threats, it said in a press release.
"The war against Ukraine has demonstrated that cyberattacks are an inseparable element of modern military campaigns," said Deputy Defense Minister Margiris Abukevičius. "Bearing that in mind, we have to prepare and build up capabilities for safeguarding our key networks, during war and peace alike, in advance."
"The three months of the operation in Lithuania offers a wealth of intelligence and skills to all participants," he added.
The operation involved a US CYBERCOM team and specialists from the National Cyber Security Center and the IT Service under the Defense Ministry.
"This hunt forward operation is a great example of how cyber is a team sport, and we have to play it together," US Army Major General Joe Hartman, the commander of the Cyber National Mission Force, the organization that deploys hunt forward teams for US CYBERCOM, was quoted as saying in the press release,
"With these missions, we see a broader scope of how these bad actors are trying to attack important government networks," he said.
Lithuania and the US "partner closely on cyber defense", the ministry said.
"The Regional Cyber Defense Centre established in Lithuania last summer serves as the main platform for practical Lithuanian-American cooperation, and it has already been joined by Ukraine and Georgia," it said.
It was the first hunt forward operation Lithuania has carried out with a US CYBERCOM team. The US has conducted such cyber defense operations in other European countries before.