Kamworor reclaimed the New York title he won in 2017 in two hours eight minutes and 13 seconds and Jepkosgei surprised four-time champion Mary Keitany, winning her marathon debut in 2:22:38.
Kamworor, training partner of world fastest marathoner Eliud Kipchoge, took command in the final two miles for the victory over compatriot Albert Korir (2:08:36) and Ethiopian Girma Bekele Gebre (2:08:38).
Defending champion Lelisa Desisa of Ethiopia dropped out of the race about the seventh mile.
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Desisa had been attempting the difficult task of trying to win again just four weeks after claiming the world championship title in the extreme heat of Doha.
Jepkosgei separated herself from Keitany, the defending champion, with five kilometres to go.
Keitany, who had won in 2014, 2015, 2016 and 2018, finished in 2:23:32 with Ethiopian Ruti Aga third in 2:25:51.
Swiss Manuela Schar routed the field in the women's wheelchair competition, winning her third consecutive title in 1:44.20 for a four-minute victory over American Tatyana McFadden.
American Daniel Romanchuk repeated as men's wheelchair champion, clocking 1:37:24 to defeat Swiss Marcel Hug by a second. Britain's David Weir took third.
More than 52,000 runners competed in the race in near perfect marathon conditions.
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