"My colleagues from the (Liberal Movement's parliamentary) group have received negative test results, but I am joining the ranks of the infected," Cmilyte-Nielsen wrote on Facebook, adding that she had developed no symptoms of COVID-19.
The Seimas carried on with plenary meetings this week despite several MPs having tested positive for the virus.
The speaker insists that she followed safety precautions and recommendations.
Karoblis went into self-isolation after his test result came back positive, the Defense Ministry confirmed.
"The minister is well, with no coronavirus symptoms," Vita Ramanauskaite, his spokeswoman, told BNS.
Over 40,000 people have tested positive for the coronavirus in Lithuania so far and 10,000 of them have recovered.
A total of 341 coronavirus-infected people have died.