SEOUL, South Korea (AP) — Some of the heaviest rain in decades swamped South Korea’s capital region, turning Seoul’s streets into car-clogged rivers and sending floods cascading into subway stations. At least nine people were killed — some drowning in their homes — and six others were missing, with more rain forecast, officials said Tuesday.

More than 45 centimetres (18 inches) of rain was measured in Seoul’s hardest-hit Dongjak district from Monday to Tuesday evening. Precipitation in the area exceeded 14 centimetres (5.5 inches) per hour at one point Monday night, the highest hourly downpour measured in Seoul since 1942.

Deserted cars and buses were scattered across streets as the water receded on Tuesday. Workers cleared uprooted trees, mud and debris with excavators and blocked off broken roads. Landslide warnings were issued in nearly 50 cities and towns, and 160 hiking paths in Seoul and mountainous Gangwon province were closed.

Emergency crews worked overnight to restore most subway service as of Tuesday morning. A route linking towns north of Seoul was temporarily shut before reopening Tuesday evening as continuing rain flooded some stations.

Dozens of roads, including major expressways near the swollen Han River, were closed because of rising water levels or partial flooding.

“The heavy rainfall is expected to continue for days … we need to maintain our sense of alert and respond with all-out effort,” President Yoon Suk Yeol said at the government’s emergency headquarters.

The military was prepared to deploy troops to help with recovery efforts if requested by cities or regional governments, Defense Ministry spokesperson Moon Hong-sik said.

The rain began Monday morning and strengthened through the evening.

By nightfall, people were wading through thigh-high waters in streets in Gangnam, one of Seoul’s most bustling business and leisure districts, where cars and buses were stuck in mud-brown waters. Commuters evacuated as water cascaded down the stairs of the Isu subway station like a waterfall. In the nearby city of Seongnam, a rain-weakened hillside collapsed into a university soccer field.

Rescue workers failed to reach three people -– two sisters in their 40s and a 13-year-old girl -– who called for help before drowning in a basement home in the Gwanak district of southern Seoul on Monday night. Another woman drowned in her home in the nearby Dongjak district, where a public worker died while clearing fallen trees, likely from electrocution. Choi Seon-yeong, an official from the Dongjak district office, said it wasn’t immediately clear whether the death was caused by a damaged power source or equipment the man was using.

Three people were found dead in the debris of landslides and a collapsed bus station in the nearby cities of Gwangju and Hwaseong.

Four people were missing in southern Seoul’s Seocho district, the home of Yoon, who, according to his office, spent hours on the phone receiving briefings and issuing instructions overnight as rain flooded streets near his high-rise apartment complex.

Nearly 800 buildings in Seoul and nearby cities were damaged and around 1,380 people were forced to evacuate from their homes as of Tuesday evening, the Ministry of the Interior and Safety said.

The country’s weather agency maintained a heavy rain warning for the Seoul metropolitan area and nearby regions on Tuesday and said precipitation may reach 5 to 10 centimetres (2 to 4 inches) an hour in some areas. It said around 10 to 35 centimetres (4 to 14 inches) of additional rain was expected across the capital region through Thursday.

Rainstorms also pounded North Korea, where authorities issued heavy rain warnings for the southern and western parts of the country. North Korea’s official Rodong Sinmun newspaper described the rain as potentially disastrous and called for measures to protect farmland and prevent flooding on the Taedong River, which flows through the capital, Pyongyang.