Two Ugandan opposition legislators say their residences have been attacked by people who lobbed explosive devices.

The lawmakers, Allan Ssewanyana and Robert Kyagulanyi, said Tuesday they believe their lives are at risk because of their opposition to plans to extend the long-time President Yoweri Museveni's time in office.

The members of parliament said no one was hurt in the attacks Monday night.

Government spokesman Ofwono Opondo said opposition members may be launching grenade attacks "to frame" the government.

Tensions are rising in Uganda as opposition leaders try to mobilize support against legislation to remove an age limit in the constitution that bars anyone over 75 from becoming president.

President Yoweri Museveni, 73 and in power since 1986, is ineligible to seek re-election in 2021 if the age barrier stays.