By Kieran Guilbert

DAKAR (Thomson Reuters Foundation) - Food aid will be doubled for people uprooted by Boko Haram violence in southeast Niger after recent attacks forced 50,000 people to flee their homes, the United Nations' World Food Program (WFP) said on Tuesday.

Boko Haram earlier this month seized the town of Bosso in Niger's Diffa region, killing 32 soldiers in the Islamist group's deadliest assault in the country since April last year.

The militants have recently ramped up attacks in Diffa, home to at least 250,000 uprooted Nigeriens and Nigerian refugees, and many people have been displaced several times, the WFP said.

"Many people have walked from 10 km to 40 kms (6 to 25 miles). They are arriving in a state of shock, and urgently need food, shelter, water – assistance with their most basic needs," said Belkacem Machane, WFP Niger deputy country director, in a statement.

"They have now reached the end of their rope," Machane said.

The WFP plans to scale up its response to help more than a quarter of a million people in Diffa, where some 450,000 people - around two-thirds of the region's population - face hunger.

A lack of funding, widespread displacement and the imminent lean season mean hunger is likely to worsen, Machane said.

Many of those in need live in makeshift huts alongside the country's main highway, yet some of the recently displaced are scattered across Diffa, said international medical charity Medecins Sans Frontieres (MSF).

The U.N. refugee agency UNHCR said last week that the 50,000 newly displaced had fled Bosso in various directions.

"Some families are in the middle of nowhere, and the insecurity means it is difficult to reach them with aid," Elmounzer Ag Jiddou, MSF's head of mission in Niger, told the Thomson Reuters Foundation.

"Our biggest concern is lack of water ... the weather is extremely hot and many people find themselves with essentially no access to water, and with no food and or shelter," he added.

Niger's President Mahamadou Issoufou told the Thomson Reuters Foundation last month that Boko Haram had destroyed schools and health clinics, paralyzed the region's economy and caused a "catastrophic humanitarian situation".

The militant group has killed more than 15,000 people and displaced more than 2 million in the West African states of Cameroon, Chad, Niger and Nigeria during a seven-year campaign to carve out an Islamist caliphate.

Along with Chad, Cameroon, Nigeria and Benin, Niger has contributed troops to a 9,000-strong regional task force dedicated to fighting the group.

(Reporting By Kieran Guilbert, Editing by Katie Nguyen; Please credit the Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking, corruption and climate change. Visit news.trust.org)