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

The authority paused the process nationwide expressing concern about 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 has set itself the target of announcing the results by the end of Sunday.

In its Friday evening update, the commission said that following a review of the situation and consultations with relevant law enforcement agencies “the security threat to the electoral process has been contained and the necessary measures have been put in place to enable the process to continue”.

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

Earlier on Friday, 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 tallying 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. He also said that his own party’s tabulation of the results showed that he had won.

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”.