Mukherjee told PTI that two candidates - Robert Romawia Royte of opposition alliance United Democratic Front (UDF) and an independent nominee Vanlalngaia filed nominations today.
The ruling Congress nominee C L Ruala and Aam Aadmi Party candidate M Lalmanzuala had filed their nominations on Thursday, she added.
Meanwhile, only two nominations were filed for the by-election to the Hrangturzo Assembly seat to be held simultaneously with the Lok Sabha polls, Dr Franklin Laltinkhuma, deputy commissioner of Serchhip district, said.
The UDF constitutes of eight parties -- Mizo National Front (MNF), Mizoram People's Conference (MPC), Zoram Nationalist Party (ZNP), Maraland Democratic Front (MDF), the Hmar People's Convention (HPC), Paite Tribes Council (PTC), BJP and NCP.