Dec 5 (Reuters) - Five people were killed and at least 15 arrested after Myanmar security forces in a car rammed into an anti-coup protest on Sunday morning in Yangon, local news portal Myanmar Now reported.

The opposition's shadow government said it was heartbroken to see peaceful protesters crashed and shot to death.

"We will strongly respond to the terrorist military who brutally, inhumanly killed the unarmed peaceful protesters," the National Unity Government's defence ministry said in a statement on social media after Sunday's attack.

In the incident, a "flash mob" protest in Yangon, Myanmar's largest city, was rammed minutes after it started, witnesses said.

The military has said that protesters who have been killed instigated the violence.