West Ham have announced the signing of Spanish striker Lucas Perez from Arsenal, confirming the 29-year-old's arrival on a three-year contract.
Perez becomes the eighth player to join West Ham ahead of the 2018-19 season, and he will compete with fellow new signing Andriy Yarmolenko for a place in Manuel Pellegrini's starting line-up.
The left-footed forward spent last season on loan at his former club Deportivo La Coruna and scored eight goals in 35 LaLiga appearances, but said he was looking forward to helping West Ham improve on their 2017-18 Premier League finish of 13th.
"I'm very happy to be here at such an historic club," he told the club's official website.
"I'm very excited, as West Ham are giving me the chance to stay in the Premier League and I'm very happy to be part of this new project.
"West Ham have great fans and play in an amazing stadium, so to sign here brings me great joy. I'm very motivated."
Arsenal paid a fee of £17million to sign Perez from Deportivo La Coruna in August 2016 but he is reported to have cost West Ham just £4m, with a potential £1m payable in add-ons.
The former Rayo Vallecano forward paid tribute to the Arsenal supporters in a message on his Twitter account, saying: "They always showed me affection and love from the first time I arrived in London.
"I also want to give my thanks to my team-mates and to the staff of this club for giving me the opportunity to make my debut in one of the best leagues in the world and win the FA Cup."
West Ham director of football Mario Husillos, who added Perez's name to a list of signings that includes Yarmolenko, Ryan Fredericks, Lukasz Fabianski, Issa Diop, Jack Wilshere, Fabian Balbuena and Felipe Anderson, underlined the Spaniard's versatility.
"He is a very experienced player that Manuel and I both know well from Spain," said Husillos.
"He has great technical quality, and can play as both the main striker or the second striker in a deeper role. He scores goals, but can also create them and link well with the midfielders.
"His style is different from the other strikers we have available to us, and that gives the manager more options for our attacking play."