MEXICO CITY — Heavy seasonal rainfall has sparked deadly mudslides and widespread flooding across Central America and Mexico’s southeast, killing at least 50 people and displacing more than half a million.

In Guatemala, rescuers citing the possibility of new mudslides called off the search for 15 people who remained missing after a highway mudslide that killed 45 others on Sunday.

In Mexico, the Red Cross said more than 600,000 have been displaced in five states as several rivers flooded towns and villages, mostly in the states of Veracruz and Tabasco. Seven people have reportedly died as a result of the floods.

Many residents of the affected regions are refusing to leave their homes and belongings.

“”This has been an extraordinarily different and extraordinarily rainier year than any other,”” President Felipe Calderon said this week while visiting Tabasco’s flood-threatened capital of Villahermosa. Calderon said anti-flooding measures in recent years have helped but that “”more must be done.””

Guatemalan President Alvaro Colom declared a state of emergency and a period of national mourning, saying in a televised message that in “”102 days of aggression from climate change,”” 253 Guatemalans have died and hundreds of thousands have been evacuated or displaced.

Guatemala was still recovering from Tropical Storm Agatha, which killed 165 people in May. The current rainy season has been called the heaviest in the country in 60 years.

Deaths related to heavy rainfall this season have also been reported in El Salvador, Honduras, and Nicaragua. The downpours have come during what is usually the heaviest part of the rainy season for the region, August and September. Seasonal rainfall ends roughly by the end of October.

Guatemala’s government said festivities celebrating independence on Sept. 15 — in particular, traditional torch processions along highways — would be canceled or muted because of the mudslide.