Lawmakers brawled in Uganda's parliament for a second day running on Wednesday over a fiercely disputed move to change the constitution to let long-ruling President Yoweri Museveni run for re-election after age 75.

MPs exchanged blows and kicks, with some using microphone stands as crude weapons in the melee, and at least two female lawmakers were carried out of the chamber after collapsing, a Reuters journalist on the scene said.

At least 25 MPs opposed to the proposed constitutional amendment to prolong Museveni's tenure were forcibly ejected on orders of the speaker for involvement in fighting on Tuesday. All other like-minded MPs then walked out.

Under the existing constitution, eligibility to stand as a presidential candidate has an age ceiling of 75 years. That makes Yoweri Museveni, 73, in power for more than three decades, unqualified to seek re-election at the next polls in 2021. Removing the age cap would clear that hurdle.