South Korea's second-quarter economic growth hit the lowest in seven quarters due to sluggish private consumption caused by the deadly ferry sinking disaster, central bank data showed Thursday.

Real gross domestic product (GDP), the broadest measure of economic performance, increased 0.6 percent in the second quarter from three months earlier after growing 0.9 percent in the previous quarter, according to the Bank of Korea (BOK).

It was the lowest since 0.4 percent tallied in the third quarter of 2012. The quarterly GDP growth stayed below the one percent level for three straight quarters. From a year earlier, the real GDP expanded 3.6 percent in the second quarter.

The yearly GDP growth continued to accelerate from 2.1 percent in the first quarter of last year to 3.9 percent in the first quarter of this year, before falling to 3.6 percent in the second quarter.

South Korea's economic growth sped up last year as the government unveiled a large-scale extra budget plan and sought to bolster the lackluster housing market.

The economy began faltering from the second quarter as one of the country's worst maritime disasters weighed down on private consumption.

The ferry Sewol capsized and sank off the southwestern coast on April 16, leaving more than 300 people, mostly high school students, dead or missing. Consumers refrained from entertainment and travel as the entire country mourned over the tragedy.

Private consumption, the economy's main growth engine, reduced 0.3 percent during the April-June period due to weak demand for both goods and services. It was the lowest in 11 quarters.

Facility investment expanded 1.3 percent in the second quarter after falling 1.9 percent in the first quarter, but investment growth in the construction sector declined from 5.1 percent to 0.6 percent in the cited period.

Brisk exports relieved the weak domestic demand. Exports of goods and services, which account for about half of the economy, increased 1.9 percent in the second quarter after rising 1.5 percent in the prior quarter due to solid demand for LCD and chemical products. Imports gained 0.8 percent in the quarter.

Intellectual property investment tumbled 4.2 percent in the second quarter after jumping 6.5 percent in the prior quarter due to patent-related royalty payment to overseas.

Gross domestic income (GDI), which gauges all income earned while producing goods and services, advanced 1.3 percent during the quarter, higher than a 0.9 percent gain in the prior quarter due to improved terms of trade.

On the production front, output in the manufacturing and construction sectors rose 1.1 percent and 0.4 percent respectively in the second quarter from three months earlier.

Production in the service industry increased 0.7 percent during the quarter, but output in restaurant, lodging and transport sectors declined on negative effect from the ferry disaster.

Production in the electricity, gas and tap water industries decreased 2.3 percent as heating demand weakened in the warmer temperature.