The treatment of about 1.1mn Muslim Rohingyas in Myanmar has become the biggest challenge for national leader Aung San Suu Kyi, who has been accused by Western critics of not speaking out on behalf of a minority who have long complained of persecution.
In the days since, clashes between Myanmar security forces and the Rohingya insurgents have killed close to 100 people.
Rohingya have been fleeing Myanmar to Bangladesh since the early 1990s and there are about 400,000 in the country, where they are a source of tension between the two nations who both regard them as the other country's citizens.
Later, media reports emerged saying Myanmar security forces used disproportionate force and displaced thousands of Rohingya villagers, destroying homes with mortars and machine guns.
We hope that the worldwide community would wake up and heedPope Francis's call and act immediately by mounting pressure on the Myanmar government so that such state-sponsored violence on the minority Rohingya community stops once and for all.
According to the government, five members of a family from the Daignet minority were killed at the weekend when insurgents attacked their village.
The Rohingya are reviled in many parts of Myanmar, with most refused citizenship, while their ability to move, work and receive basic services is tightly controlled.
More than 8,700 Rohingya have fled from Myanmar into Bangladesh since the attacks, Zeid said in a statement.
Satellite imagery analyzed by New York-based Human Rights Watch showed widespread burnings in at least 10 areas in northern Rakhine since the Friday raids, the group said.
Turkey's President Recep Tayyip Erdogan accused the worldwide community of ignoring the suffering of Myanmar's minority Muslim community, even as the worst violence in years has broken out in Rakhine state.
There are already nearly 400,000 Rohingya refugees in Bangladesh in squalid camps near its border with Myanmar.
Thai immigration police told Reuters in May that people-smuggling across the border from Myanmar to Thailand was rising despite the crackdown. "We took an oath to save Arakan [another name for Rakhine], even if it is with sticks and small knives", one insurgent in Bangladesh near the border told AFP.
The UN has said the government's response to those attacks could amount to ethnic cleansing.