"Secretary Delfin Lorenzana is on his way back from Russian Federation with the President to personally oversee the situation", DND public affairs office chief Arsenio Andolong said in a statement Wednesday. "I have to do it to preserve the republic".
"The whole of Marawi city is blacked out, there is no light, and there are Maute snipers all around", Lorenzana said in the news conference in Moscow, which was broadcast live in the Philippines.
Duterte will cut short his trip and fly back to deal with the situation in the south, said his foreign secretary, Alan Peter Cayetano.
The Russian news agency Tass quoted officials saying Duterte told Putin he was counting on Russia to supply weapons to counter terrorism in the Philippines.
Arevalo said troops had cleared militants from a hospital, the city hall and Mindanao State University.
Duterte repeatedly threatened to impose martial law early in his term as he faced criticisms on his war against illegal drugs, which led to thousands of deaths. He is a commander of the Abu Sayyafmilitant group and was wounded by a military airstrike in January.
Arevalo added that they still have no information on whether Maute Group members have casualties in the series of gunbattles with government security forces in Marawi City.
The fighting broke out after a joint team of the military and police tried to serve a warrant of arrest on a leader of the Abu Sayyaf group, Lorenzana said.
The US State Department offers a $5-million bounty for Hapilon's capture.
Hapilon, an Arabic-speaking Islamic preacher known for his expertise in commando assaults, pledged allegiance to the Islamic State group in 2014. They had learned Isnilon Hapilon was in the area, but according to Lorenzana, the military had not expected him to be backed up by "more or less 100 fighters" - many of whom were members of another ISIS-linked organization, the Maute Group.
Most of the people of Lanao del Norte made a decision to remain in Marawi City (population: 200,000) "to protect their homeland from destruction" urging local leaders, peace advocates and the warring parties to spare Marawi City.
The Maute Group killed a cop and a security guard, and then took hostages - 8 patients, 49 construction workers, and 21 hospital staff - on Tuesday when they forced hospital staff to treat two of their wounded colleagues.
"We're trying our best to contain the situation", Herrera said by telephone, adding that troops were moving carefully to avoid hitting civilians in the area of the fighting.
Duterte tagged on September 3, the Abu Sayyaf, an Islamic militant group from the southern Philippines notorious for kidnappings, as a possible suspect in a deadly blast in his home town of Davao.
Late last month Philippines security forces claimed they killed 36 Maute fighters and captured the rebels' base during a three-day operation.
Troops and special paramilitary police officers were deployed to the city after residents in a nearby village raised the alarm and appealed for help.