This paper examines the impact of the rapid development of generative artificial intelligence (GenAI), particularly large-scale language models (LLMs), on the integrity and copyright of journalism. We analyzed over 40,000 news articles from various sources, including major media outlets, regional media, and university presses, to identify trends in the use of GenAI. We then analyzed the actual use of GenAI using three AI detectors. Our analysis revealed a significant increase in GenAI use in recent years, particularly in regional vernacular and university presses. Sentence-level analysis revealed that LLMs are frequently used in the introduction of news articles, while conclusions are largely hand-written. Linguistic analysis revealed that GenAI enhances word richness and readability, but reduces formality, leading to a uniformity in writing style, particularly in regional presses.