China's trade shrank in April in a worrisome sign for official efforts to reverse a slowdown in the world's second-largest economy.

Customs data Sunday showed exports contracted by 1.8 percent from a year earlier to $172.7 billion, falling back into negative territory after March's temporary burst of 11.5 percent growth. Imports plunged 10.9 percent to $127.2 billion after the previous month's 13.8 percent contraction.

China's economic growth slowed to a seven-year low of 6.7 percent in the first quarter of the year. Manufacturing and other activity have been lackluster despite government stimulus efforts that include a boost in bank lending and an easing of controls on real estate sales.