The Hammers confirmed the deal on their official website, revealing in a statement that the Nigerian striker had moved to the club on loan until the end of the season.
The East Londoners have the option to sign the forward permanently at the end of the campaign should they so desire.
The powerful Emenike—who shone briefly for Nigeria at the 2014 World Cup in a 1-0 victory against Bosnia-Herzegovina—spent the first half of the season on loan with Al-Ain in the United Arab Emirates, scoring seven times.
The attacker has featured 37 times for the Super Eagles, although he called time on his international career last season, however, at the Boleyn Ground he will link up once again with Victor Moses, a player alongside whom he won the Africa Cup of Nations in 2013.
Emenike may ostensibly provide competition for the likes of Diafra Sakho and Andy Carroll—both of whom have had injury concerns so far this season—although he has the pace, the power and the versatility to command a first-team spot should he adapt to the English game.
Ahead of the midweek fixtures, the Hammers sit sixth in the Premier League table, only one point behind fifth-placed Manchester United and six behind Tottenham Hotspur, who currently occupy the fourth Champions League spot.
Speaking earlier this month, as per the Daily Mail, coach Slaven Bilic confirmed that he is encouraging his players to consider the prospect of qualification, and may see Emenike as a valuable addition as they seek to secure an unlikely top-four finish.
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