The organizer said an undetermined number of protesters, some armed with homemade weapons, were arrested in the town known for fiercely resisting government forces.
Demonstrators continued to take to the streets on Thursday across the country, including in the largest city of Yangon and the southern city of Dawei.
Government ministries will resume full operations soon, junta spokesman Brigadier Zaw Min Tun told a news conference in the capital, Naypyitaw.
"We can not really do what we want because we have shared borders and we need to live and rely on each other on many areas", said Thai Prime Minister Prayuth Chan-ocha, who had himself seized power in a 2014 coup when army chief, before taking on his current civilian role in 2019.
"People will not wait for CRPH to act", the minister said in a video call with Reuters. "The CRPH can not stop the possible armed resistance by the people, from the people".
AAPP has said 2,847 people were now being held in detention.
Myanmar security forces have arrested a model and actor who had spoken out against the coup, his sister told Reuters, as activists placed shoes filled with flowers in parts of Yangon to commemorate dead protesters.
In addition, arrest warrants have been issued for hundreds of people, with the junta this week going after scores of influencers, entertainers, artists and musicians. He had condemned the military takeover and pledged support for Suu Kyi.
The country's most famous comedian, Zarganar, was arrested on Tuesday, media reported.
US Secretary of State Antony Blinken said in a statement that the sanctions are a clear signal that Washington will keep increasing pressure on the military's revenue streams until it ceases its violence and releases all those unjustly detained.
Overseas, diplomatic tussles emerged again on Wednesday.
London ambassador Kyaw Zwar Minn has broken ranks with the ruling junta in recent weeks, calling for the release of detained civilian leader Aung San Suu Kyi.
"I have been locked out", Ambassador Kyaw Zwar Minn told Reuters outside the embassy in central London.
In a statement read on his behalf Thursday in front of the building, Kyaw Zwar Minn said that embassy personnel were being "threatened with severe punishment" if they refused to work for diplomats loyal to the military government.
There have also been similar counter claims in embassies in other global centres and at the United Nations. MBT said its service was halted by a break in the line between Yangon and Mandalay, the country's two biggest cities.
A group representing the ousted civilian government said yesterday it has gathered 180,000 pieces of evidence showing rights abuses by the junta including torture and extrajudicial killings.
Britain has sanctioned members of Myanmar's military and some of its business interests in wake of the coup and has demanded the restoration of democracy.
The vast majority of people back Suu Kyi's ousted government, it added.