Zambia’s electoral commission has suspended the counting of votes from Thursday’s presidential, parliamentary and local elections over alleged attacks on polling staff.

The authority said the process would be halted nationwide with immediate effect as it expressed concern over reports of violence that had “resulted in the theft of marked ballot papers in ballot boxes”.

President Hakainde Hichilema is seeking a second five-year term. Brian Mundubile is the main opposition candidate among 13 challengers.

The electoral commission had previously set itself the target of announcing the results by the end of Sunday.

Counting got under way immediately after polls closed on Thursday but no official results had been declared when the halt in the count came into effect.

In Friday’s statement the commission said it would review the decision to suspend vote counting within the next 24 hours.

Just hours before the commission’s statement, Mundubile expressed “grave concern” over delays in the announcement of presidential results, warning that the delay could create opportunities for interference or manipulation.

He cited what he described as “deeply troubling reports” from several areas, including alleged military involvement at totalling centres and allegations concerning the movement of ballot boxes.

He called for the immediate publication of results polling station by polling station, protection of the chain of custody and investigations into the reported incidents.

Hichilema also issued a statement urging Zambians to “remain peaceful, patient and patriotic as we await the official outcome from those entrusted with managing the vote”.