Activity in China's manufacturing sector expanded again in September, a new official survey has shown. Analysts say that may indicate sustained positive momentum.

China's official Purchasing Managers' Index stood at 50.4 in September, in line with market expectations. That's also identical with the previous month's level. Analysts say that a reading above 50 shows growth on a monthly basis.

"September's PMI data remained flat from the preceding month. Manufacturing and market needs both grew steady. As the structural adjustment further promote, manufacturing sector is stabilizing at the present stage," Zhao Qinghe, senior statistican with National Bureau of Statistics, said.

In September, output edged up to 52.8 from 52.6 in August, but the index for total new orders slipped to 50.9 from 51.3.

Sectors like high-tech, auto manufacturing and shipbuilding showed strong expansion.

A sub-index for smaller firms fell, while performance at larger companies improved, a sign that the government's dependence on big state firms for growth this year has not changed.

"The overall economy is grow steady. But, do not only see the positive sign. The country is now entering a new phase of development. Our main target is transformation, especially supply-side reform," Cai Jin, vice president of China Federation of Logistics Purchasing, said.

Analyst say the pattern over the past few months suggested sustained economic growth, but a growing dependence on government spending and an overheated property market may pose risks later this year.