Some took to Twitter to show screenshots of missed calls.

“They must think we are idiots like them,” said PPBM deputy president Mukhriz Mahathir, as he posted a screenshot showing dozens of missed calls from the United States.

Many PKR leaders said they experienced the same, with vice-president Tian Chua blaming it on “Umno/BN black op strategists”.

“My phone has been jammed with non-stop computer-generated calls originating from the US since 7:30 this morning. Yes it irritates me, but what would they achieve?” he asked.

DAP leaders too said they were receiving calls from unknown numbers.

“Umno/BN dirty tricks are at work today with mobile telephones of key DAP leaders throughout the country sabotaged and disabled by endless incoming calls from the United States, since 7.30am in some cases and 8am in others,” said party veteran Lim Kit Siang.

However, a number of Barisan Nasional leaders have also claimed their mobile phones have been inundated with calls from unknown US numbers since this morning.

FMT is trying to get the Malaysian Communications and Multimedia Commission for a response.