KARACHI: Polling is currently underway for by-elections on one national and two provincial assembly seats amid tight security on Sunday. According to the details, it is being held on national Assembly seat NA-247, Sindh Assembly seat PS-111 and Khyber Pakhtunkhwa Assembly seat PK-71 today. The polling time is from 8am to 5pm. Pakistan army personnel supervised the transporting of polling material to the polling stations, media reported. However, there are about 546,451 registered voters in NA-247 and 178,965 registered voters in PS-111 according the Election Commission of Pakistan (ECP). Read more: By-election: over 100 in race for 35 seats The ECP also stated that about 12 candidates are contesting for the NA-247 seat while 11 for the Sindh Assembly seat. Previously, President Dr Arif Alvi left the NA-247 seat in Karachi while PS-111 was vacated by Sindh Governor Imran Ismail.