Pupils who sat for their UPSR English examination on Thursday will have to re-take their papers, according to Second Education Minister Datuk Seri Idris Jusoh .
He said the ministry confirmed on Thursday morning that the English 0141 and 0142 papers had been leaked.
Vernacular school pupils will not be affected as they sit for different English papers.
"If possible, we're aiming to have the re-sit on Sept 30, the same day as the rescheduled Science papers.
"This is a serious matter, and we will make sure that the sternest action is taken against those responsible for the leak.
"I apologise to all the parents and pupils involved," he told reporters here on Thursday.
This is the second confirmed leak for the UPSR.
On Wednesday, the Malaysian Examinations Syndicate said that the Science papers had been postponed to Sept 30 as the questions were leaked on social media.
However, the syndicate was silent on claims that the UPSR papers for Bahasa Melayu and Mathematics were leaked as well.
When asked, Idris said that such claims were unsubstantiated.
"We cannot simply announce such leaks without investigating the matter, these (English and Science) are the only papers proven to have leaks.
"We have already lodged police reports over the confirmed leaks.
"We will also set up a committee on the matter, to look into the technology and security measures involved to make sure that this does not happen again," he said, adding that the committee would comprise "high profile" members.
Idris also said that such incidents proved that the current education system was too exam-oriented.
"This is why we introduced the school-based assessment system, to take this pressure off.
"Students have become too focused on just the examinations, that they're willing to cheat," he said.
A total of 473,175 pupils are sitting for the UPSR this year at 8,299 examination centres nationwide.