Integrated intensity map of¹² CO with the color scale range from 3σ (1.9 K km s⁻¹). The black contour shows the ¹³CO emission with the contour level of [1.75, 3.5] (5σ = 1.75) K km s⁻¹ . The velocities are both integrated within [−14, −2] km s⁻¹. The purple dashed ellipse and contours show the size and intensity with the contour level of [12, 15, 18] K of Urumqi λ 6 cm radio continuum emission. The orange and green circles represent the LHAASO source 1LHAASO J0428+5531 (Cao et al. 2024), with orange indicating KM2A components and green denoting WCDA components. The CO emission aligns well with the radio shell and is spatially coincident with the LHAASO source. The yellow star markers represent massive OB stars, with the red labels indicating the spectral types and the green labels displaying the distances in kiloparsecs.