embedded filaments appear to be directed towards the location of AFGL 5157 and the emission peaks (i.e., H[ii]{} region and dense core) in and around the region. In Figure \[fig1\]b, the position of the previously detected H[ii]{} region [from @torrelles92b] is marked by a star, which is embedded in the dense NH$_{3}$ core reported by @torrelles92b. The quantitative information of these filaments is presented in Section \[ssubsec:u2\].

Using the [*Spitzer*]{} 8.0 $\mu$m image (resolution $\sim$2$''$), Figure \[fig1\]c shows a zoomed-in view of the area containing AFGL 5157. In Figure \[fig1\]c, the location of the infrared shell is also indicated by the emission contour at 8.0 $\mu$m (see also Figure \[fig1\]a). Furthermore, the absorption features against the Galactic background in the 8.0 $\mu$m image are seen in the Galactic northeast to southwest directions around the infrared shell. It enables us to identify the infrared dark clouds (IRDCs) in AFGL 5157 (see arrows in Figure \[fig1\]c). In addition to the IRDCs and the infrared shell, the [*Spitzer*]{} 8.0 $\mu$m image also reveals noticeable diffuse emission, which is highlighted by arrows in Figure \[fig1\]c. In Figure \[fig1\]d, the sub-mm image at 160 $\mu$m (resolution $\sim$12$''$) traces the bright emission toward the IRDCs, and 