Japan's exports grew in September for a second straight month, reflecting the nation's gradual recovery from March's earthquake and tsunami as auto production returns to pre-disaster levels.

Exports rose 2.4 percent from a year earlier to 5.98 trillion yen ($78.2 billion), pushing Japan back into a trade surplus after registering a deficit in August, the finance ministry said.

The gain beat market expectations for a 1.0-percent expansion and came after a 2.8 percent rise in exports in the previous month.

However, imports soared 12.1 percent to 5.68 trillion yen, rising for the 21st straight month, mainly due to higher energy prices.

It left a trade surplus of 300.4 billion yen ($3.9 billion), also bigger than market expectations for 199.5 billion yen.

But the trade surplus was 61.2 percent lower than the level seen last year, reflecting the high cost of energy as Japan ramps up imports of fossil fuels to make up for the shortfall in power supply, with many of the country's nuclear plants still offline in the wake of the Fukushima disaster.

The rebound in exports showed that Japan was "on the way to a moderate recovery," said Yasunari Ueno, chief market economist at Mizuho Securities.

Leading the recovery, auto exports rose 4.9 percent while exports of auto parts jumped 11.5 percent, the finance ministry said.

Leading automaker Toyota Motor's global production recovered to pre-tsunami levels in September, two months earlier than forecast, local media said, before Thai floods forced the temporary shutdown of factories there.

Japanese shipments of semiconductors and electronics parts were still down 9.0 percent from the previous year, according to the ministry data.

Looking ahead, worries remain for Japan Inc. after the yen reached a new record against the dollar Friday.

Major foreign markets such as the United States and Europe tend to stagnate ahead of the Christmas sales season, also pressuring exporters.

The Cabinet Office last week downgraded its view of the economy for the first time in six months as an overseas slowdown weighed on output and exports, while a strong yen further clouded the outlook.

In its monthly report for October, it lowered its assessment of exports, industrial production and personal consumption while warning that the effects of deflation still pose a threat.

For the April-September fiscal half year, Japan's exports fell 3.8 percent on year, the first drop in four halves, mainly on auto, semiconductor and plastic exports that were hit hard by the March disasters.

Imports for the same period rose 12.1 percent on soaring energy costs, leaving Japan in a trade deficit for the period.