GENEVA, Oct 15 (Reuters) - The first of three planned aid flights landed in Uzbekistan on Friday, carrying shelter supplies to be taken by truck for tens of thousands of displaced people in Mazar-i-Sharif, in northern Afghanistan, the U.N. refugee agency said. "The first flight landed in Termez," UNHCR spokesperson Babar Baloch told Reuters in a message from Kabul, referring to the Uzbek border town. The flight carried 32 tonnes of relief supplies from UNHCR"s warehouse in Dubai - mainly shelter items, kitchen sets, plastic tarpaulin - or one-third of the cargo planned in the operation, he said. In all they will be distributed to 18,000 families or 126,000 people, he added. "We are racing against time to give people assistance before winter ... If you are out there in the open without any help that cold can kill you," Baloch told a briefing earlier in the day.