Assam voted on September 13 for by-polls to 3 Assembly constituencies.
The Congress and the AIUDF bagged one seat each in Assam Assembly by-election, while the BJP is leading in another.
The AIDUF's Abdur Rahim Ajmal won the Jamunamukh seat defeating the Congress' Bashir Uddin Laskar by 22,959 votes, election office said.
AIUDF President Badruddin Ajmal's son Abdur Rahim Ajmal retained the seat polling 62,153 votes, while his nearest rival Laskar got 39,194 votes.
Gains for AIUDF in AssamThe ruling Congress retained Lakhipur seat as its candidate Rajdeep Goala defeated his nearest BJP rival Sanjay Thakur by 9172 votes garnering 40,090 votes, while Thakur got 30918 votes.
In Silchar, however, BJP's Dilip Kumar Paul is ahead of Arun Dutta Majumdar of the Congress.
By-elections on September 13 were necessitated in Lakhipur seat due to the death of Rajdeep Goala's father and sitting MLA Dinesh Prasad Goala.
Election of Silchar Congress MLA Sushmita Dev and Jamunamukh AIUDF MLA Mohammad Sirajuddin Ajmal to the Lok Sabha during the last general elections necessitated the by-poll there.