TORONTO - Sun Life Financial Inc (SLF.TO) said on Wednesday it will acquire the pension business of FWD Hong Kong in the latest stage of its rapid expansion in Asia.

The Toronto-based company has embarked on a flurry of takeovers in Asia in the past three years, hoping to take advantage of the region's burgeoning middle class as they look to save and invest.

"Expanding our pension business is a key priority for our Asia operations and deepens our wealth business in the region," said Dean Connor, Sun Life's President and CEO.

The financial details of the FWD Hong Kong transaction were not disclosed.

Sun Life said the acquisition will take its Hong Kong units' assets under management to $5.8 billion.